sustainability

Article Building the Future on Lessons of Historic Reinforced Concrete

Maria Bostenaru Dan Department of Urban and Landscape Design, Faculty of Urbanism, “Ion Mincu” University of and Urbanism, 010014 , ; [email protected]  Received: 12 May 2020; Accepted: 20 July 2020; Published: 23 July 2020 

Abstract: This contribution presents the way the construction material reinforced concrete was introduced at the beginning of the 20th century, from both the technical (Hennebique system) and the philosophical points of view. The philosophy underlying the use of this material is evident in the theories on finding a language of form corresponding to tectonics, and its dialogue with timber, formulated by certain notable practicing architects of the time across . Not to be neglected are aspects relating to the conservation of material and to interventions carried out over time. In Modernist times, this meant a change from the artistic expression of . Today, it means technical adaptation. The paper addresses thus sustainability of intervention versus conservation.

Keywords: 20th century architecture; historic concrete; conservation

1. Introduction Concrete had existed since the Roman times, but it was Joseph Monier (8 November 1823 Saint-Quentin-La-Poterie–12 March 1906, ) who conceived the idea of reinforcing it, showing the idea at the Paris Exhibition 1867. Although reinforced concrete was a new material which spread during the heyday of , its language of form was sought after during the Art Nouveau period. The new material introduced at the time of Art Nouveau was iron, but the discussion on finding new forms for new materials applied equally to reinforced concrete. In many parts of Europe, unlike older buildings which are doubtless recognized as heritage, buildings from the 20th century still struggle to get this status, not being considered old enough. Also, the innovative material concrete was seen in that time as technological revolution, as we will see in this paper, but proved in history not to be an everlasting material. At that time, the material was suitable for industrial production and was also employed in industrial buildings, since the challenge of early 20th century was related to economic efficiency and industrialization. The challenges of the beginning of the century were connected to the mass movement of the population to cities, in search of work places in the context of industrialization, and this was highlighted also in the discussions (conference, films, exhibitions) of Bauhaus 100th anniversary last year (1919–2019). Today’s challenges are different and related to environmental protection. Sustainability is an issue we have to take into account when thinking today of future generations, since resources are limited. The city cannot expand anymore, and these environmental issues are building a mostly invisible fortification around the city, sometimes visible as a green belt. Intensive construction replaces extensive construction. As such, the reuse of the materials they are made of or of the whole buildings of early 20th century is one of the challenges of today, especially since concrete aged and security requirements also evolved since and are not met today anymore. The sustainability of concrete as production material was addressed in [1]. Today, some buildings present challenges of security [2] against earthquake. According to the Brundtland report in 1987, 33 years ago now, the sustainability of concrete has to be put into question. Mindes and Aitcin [3] built on this affirmation when thinking of the material included in concrete, but concentrated

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[4] look In caseinstead of demolitions, at the sustainabl somee examplesuse of concrete. with material While looking reuse have to the been history shown. of concreteSakai and employment Noguchi [4] from look Roman instead times at the and sustainable in the past use century of concrete. in parallel, While the looking same issues to the are history raised of regardingconcrete employment material fromflow, Romanbut including times and inaspects the past as century landscape in parallel, destruction the same issuesand economic are raised considerations.regarding material flow, but including aspects as landscape destruction and economic considerations. Life cyclecycle assessmentassessment is is needed, needed, and and there there are earefforts efforts to network to network internationally internationally for this, for for examplethis, for examplein the COST in the (European COST (European Cooperation Cooperation in Science andin Science Technology) and RESTORETechnology) “Rethink RESTORE Sustainability “Rethink Sustainabilitytowards a Regenerative towards a Economy”Regenerative network, Economy” including network, the circularincluding economy. the circular Historic economy. constructions Historic constructionsshall satisfy today’s shall satisfy safety today’s and energy safety regulations and energy and regulations be upgraded and be accordingly, upgraded accordingly, while maintaining while maintainingoriginal substance original in substance order to complyin order with to comply monument with protectionmonument regulationsprotection regulations but also because but also of becausematerial of sustainability material sustainability issues. In Karlsruhe issues. In the Karlsr formeruhe Institute the former for IndustrialInstitute fo Productionr Industrial at Production the Faculty atof the Architecture Faculty of is Architecture dealing now withis dealing the life now cycle with assessment the life cycle of buildings. assessment One of of buildings. the teaching One modules of the teachingrun is called modules “integral run planning” is called and“integral means planning” including and in the means initial including stages of architecturein the initial planning stages of architectureall other disciplines. planning This of canall other be extrapolated disciplines. for This existing can buildings,be extrapolated for example, for existing in seismic buildings, retrofitting, for example,as done in in the seismic research retrofitting, of the author as [5done], by includingin the research building of survey,the author economics, [5], by andincluding structural building issues survey,while performing economics, the and architecture structural projectissues while of reuse. performing the architecture project of reuse. Further to the BrundtlandBrundtland report,report, thethe EXPO EXPO (World (World exhibition) exhibition) 2000 2000 Hannover Hannover was was also also bound bound to tosustainability sustainability principles, principles, containing containing issues issues regarding regarding the usethe of use local of materialslocal materials and water. and water. The author The authorvisited thevisited EXPO the and EXPO saw and in the saw Netherlands in the Netherla pavilionnds anpavilion innovative an innovative employment employment of the principles of the principlesregarding regarding the basement-body-roof the basement-b principleody-roof principle of a building, of a building, also in concretealso in concrete [6]. Examples [6]. Examples of the ofconservation the conservation of early of buildingsearly buildings in reinforced in reinforced concrete concrete are given are given here here in more in more detail detail for Italy. for Italy. In this In thisseismically seismically prone prone country, country, it is not it is only not the only aging the ofag theing materialof the material that poses that a poses problem, a problem, but also but the loadalso thebearing load characteristics.bearing characteristics. Several studies Several on studies such characteristics on such characteristics of historic of reinforced historic reinforced concrete structures concrete structureswere carried were out carried by the out University by the University of Genoa [ 2of], Ge fornoa example, [2], for related example, to therelated restoration to the restoration and functional and functionalconversion conversion of the former of the Hotel former Colombia Hotel (1921–1926)Colombia (1921–1926) to a university to a un library,iversity or library, to the Stock or to Exchangethe Stock Exchangebuilding (1909–1912) building (1909–1912)(Figure (Figure1)[ 7] and the1) [7] Grand and Hotelthe Grand Miramare Hotel (1906–1908). Miramare (1906–1908). Although Porcheddu, Although Porcheddu,the agent of the Hennebique agent of Hennebique in Italy was basedin Italy in was the based North, in in the Turin, North, and in most Turin, works and were most concentrated works were concentratedthere, buildings there, made buildings of early made reinforced of early concrete reinforced which concrete need which repair need and repair maintenance and maintenance are found arethroughout found throughout the country, the also country, in the South,also in like the the So Risorgimentouth, like the Risorgimento bridge in Rome bridge and Viaductin Rome Corso and ViaductItalia in BariCorso [8 ].Italia Later in on,Bari we [8].Later will address on, we the will case address of a Portuguese the case of bridge a Portuguese as well. bridge as well.

Figure 1. FunctionalFunctional reconversion reconversion and and restoration restoration of of a a reinforced reinforced concrete concrete building building Hennebique. Hennebique. University librarylibrary (formerly(formerly hotel hotel Colombia), Colombia), Piazza Piazza Principe, Principe, Genova, Genova, Italy. Italy. (photo (photo M. Bostenaru, M. Bostenaru, 2012). 2012). Challenges of the conservation of industrial buildings are addressed by The International CommitteeChallenges for theof Conservationthe conservation of the of Industrialindustrial Heritagebuildings TICCIH are addressed [9]. The by charter The International [9] promotes Committeefunctional in for situ the conservation, Conservation but of accepts the Industrial reuse. Heritage TICCIH [9]. The charter [9] promotes functionalIf demolition in situ conservation, is unavoidable, but recycled accepts concrete reuse. [10] is an answer for a circular economy. Studies are beingIf carrieddemolition out is in unavoidable, Portugal, at therecycled University concrete of [10] Minho, is an using answer concrete for a circular from a economy. bridge due Studies to be are being carried out in Portugal, at the University of Minho, using concrete from a bridge due to be demolished [11]. In the Bürgerparkviertel (1996–2001) in Darmstadt, Germany, on the place of Sustainability 2020, 12, 5925 3 of 26

Sustainability 2020, 12, x FOR PEER REVIEW 3 of 27 demolished [11]. In the Bürgerparkviertel (1996–2001) in Darmstadt, Germany, on the place of dismantled industrial industrial buildings buildings for for meat meat production production (1887–1908) (1887–1908) which which were were abandoned abandoned since since 1988, 1988, new buildings buildings were were built built employing employing recycled recycled concrete concrete.. Kramm Kramm et Strigl et Strigl [12][ bu12]ilt built so both so both offices offi andces parkingand parking (Figure (Figure 2), and2), after and the after plans the of plans Hundertwasser of Hundertwasser (15. December (15. December 1928 in Vienna–19. 1928 in Vienna–19. February 2000February Queen 2000 Elizabeth Queen Elizabeth2 in Brisbane) 2 in Brisbane) the first Germ the firstan Germanhousing housingbuilding building “Die Waldspirale” “Die Waldspirale” (forest spiral)(forest spiral)(Figure (Figure 3) was3 built.) was In built. these In instances, these instances, recycling recycling concrete concrete was used, was used,after having after having been beenused beforeused before only in only road in construction road construction [13]. [13].

Figure 2.2. BürgerparkviertelBürgerparkviertel Darmstadt: Darmstadt: the the offi officece and and parking parking buildings buildings with recycledwith recycled concrete. concrete. (photo: (photo:M. Bostenaru, M. Bostenaru, 1999). 1999).

Figure 3.WaldspiraleWaldspirale Darmstadt. Darmstadt. (photo (photo M. M. Bostenaru, Bostenaru, 2005). 2005).

The materialmaterial cancan also also be be repaired, repaired, as oneas one innovative innovative technology technology being being self-healing self-healing to repair to cracks,repair cracks,as from as aging from or aging earthquakes or earthquakes [14]. Magdalini [14]. Magdalini Theodoridou Theodoridou applied applied this to buildingthis to building stone in stone a MSCA in a MSCA(Marie (Marie Skłodowska-Curie Skłodowska-Curie actions) actions) project project at Cardi atff CardiffUniversity University [15,16]. [15,16]. Research methods includedincluded thethe analysisanalysis of of historical historical written written philosophical philosophical works works (philosophy (philosophy as asresearch research method method in architecture),in architecture classification), classification and and analysis analysis ofphotographs of photographs from from the the collection collection of the of theauthor author gathered gathered over over years years (presented (presented in the in work the work mentioned mentioned at acknowledgements), at acknowledgements), literature literature review reviewincluding including primary primary literature literature from books, from journals,books, journals, and conferences, and conferences, news reports, news andreports, websites, and websites,including including databases databases on the conservation on the conservation state, biographies state, biographies of the architects of the and architects engineers and of theengineers works, ofarchive the works, research, archive visit research, of exhibitions, visit of exhibitions, own architecture own architecture internship internship in the offi cein the of Krammoffice of etKramm Strigl, etand Strigl, also editingand also of editing the author’s of the ownbooks author’s ownb and attendanceooks and attendance and presentation and presentation at relevant conferencesat relevant conferences(Riga, Milan, (Riga, Guimar Milan,ães) pertaining Guimarães) to thepertaining large subject to the of thislarge research subject including of this research networking. including networking.

2. Language for Reinforced Concrete In this paper, reinforced concrete will be regarded as a structural material, and, for this purpose, there will first be a review of Kenneth Frampton’s view of tectonics [17], followed by an analysis of Sustainability 2020, 12, 5925 4 of 26

2. Language for Reinforced Concrete In this paper, reinforced concrete will be regarded as a structural material, and, for this purpose, there will first be a review of Kenneth Frampton’s view of tectonics [17], followed by an analysis of the theories and practice of early 20th century architects employing reinforced concrete. Tectonics may also be the solution to deal with the material when intervening in historical buildings, such as Anne-Catrin Schulz’s [18] work on layers in the oeuvre of Carlo Scarpa.

2.1. Review of Kenneth Frampton’s Tectonics with Regard to Reinforced Concrete In his introduction to “Reflections on the Scope of the Tectonic”, Kenneth Frampton discusses the greater scope given to the concept of tectonics. Viollet le Duc was the first to change the view on tectonics which had existed since Ancient Greek times, introducing the logic of construction. Kenneth Frampton recognizes that the study of tectonic culture aims at mediating the priority of the given space with the constructional and structural models through which it is achieved. He identifies three vectors: “topos”, “typos”, and “tectonic” and emphasizes the independence of tectonics from style, but not from site and type. Frampton’s words are not new, however. From 1843–1852 Karl Bötticher wrote three volumes on The Tectonic of the Hellenes [19], distinguishing between ’Kernform’ (nucleus shape) and ’Kunstform’ (artistic shape), that is, what we nowadays call container and contents, or structural skeleton and ornamentation. In Bötticher’s work, ‘Kernform’ refers to the timber rafters, and the ‘Kunstform’ “the petrified beam ends in the triglyphs and metopes of the classical entablature”. This type of discourse was taken up again in essays exploring the poetics of concrete as a material, at the beginning of the 20th century. Timber was examined in the same manner, for example by István Medgyaszay, as we will later see. Bötticher’s theory was taken further by the seminal work of Gottfried Semper [20], who differentiated between lightweight and mass: tectonic/stereotomics (stereotomic meaning “solid” and “cut” in Greek and being thought to be load bearing masonry). Frampton refers to this as “constructive mass and tensile frame”. As Frampton notes, Semper’s theory was supported by the German language, where “Wand” refers to infill walls in skeleton construction and “Mauer” refers to the heavy load-bearing wall composed of artificial or natural stones superimposed and bound with mortar. Although already possible in timber, this kind of separation became evident with reinforced concrete, which allowed three types of relationship between structure and space: structural plan (with the heavy load bearing walls separating into functional units), free plan (where the two are distinct) and the ‘Raumplan’ (where spaces are connected, in a structural frame), the last named introduced by Adolf Loos. On a personal note, this is also supported by the German language, which has the word “Massivbau” meant for materials such as brick/stone and reinforced concrete, to be differentiated from timber and metal. Semper later wrote a work about materials themselves, the Stoffwechsel-theory [21], where he differentiated between wood, basketwork, and textiles, which are tensile, and stonework, brickwork, rammed earth, and reinforced concrete, which are compressive materials. However, the architects of the early 20th century identified the possibility of building the skeleton form in reinforced concrete, the wattle and daub infill type of timber. Other interdependencies exist; Frampton notes, for instance, that masonry bonds are a form of weaving. Finally, there is mention of the durability of materials; for example, mud disintegrates, and wood is ephemeral, while stone endures over time. Reinforced concrete is artificial stone. Finally, Frampton notes that Semper’s theory is rooted in the emerging science of ethnography. In fact, Ákos Moravánszky, another architecture theoretician who studied Semper as well as the early reinforced concrete theory devised by Medgyaszay, also emphasized the ethnographic influences in the Central European architecture of the early 20th century [22]. The ’Kernform’ and ’Kunstform’ of Bötticher were developed by Semper into the technical and symbolic aspects of construction, which then were related by Frampton as “representational and ontological aspects of tectonic form” [17]. In philosophy, ontology studies the nature of being. Today, it is used in computer science, as the basis for object-oriented software design by formally representing the concepts within a domain and their relationships. Frampton [17] refers to Semper, finding that the Sustainability 2020, 12, 5925 5 of 26 earthwork, frame, and roof are ontological and the hearth and infill wall are representational or symbolic. The ontological aspect thus reflects the superposition of registries [6]. Recently, Sandaker wrote an ontology of structured space [23], presented at the same conference [11] where a discussion took place during which there was a dedicated session to this work by Frampton. In his lecture in 1905 “On the likely development of architecture”, the Dutch architect Hendrik Berlage [24] also differentiated between constructive and non-constructive parts of spatial enclosure. In connecting tectonics to ontology, which is a philosophical concept, Frampton comes to Heidegger’s phenomenological work “On the Origin of the Work of Art” [25] (1956, in Poetry, Language, Thought). Here, the author reflects on the relationship between material and form, examining whether the relationship has its origin in the character of the thing [26] or that of the work of art, and “conceives architecture as having the capacity not only of expressing the different materials from which it is made but also revealing the different instances and modes by which the world comes into being: ’the temple-work, in setting up a world, does not cause the material to disappear, but rather causes it to come forth for the very first time [...] The rock comes to bear and rest and so first becomes rock; metals come to glitter and shimmer, colors to glow, tones to sing, the world to speak. All this comes forth as the work sets itself back into the massiveness and heaviness of stone, into the firmness and pliancy of wood, into the hardness and luster of metal, into the lighting and darkening of color, into the clang of tine and into the naming power of world’” [17]. The paragraph is also quoted in [27] by reflecting on the relationship between technique and art, what in architecture is always the case, between technology/engineering and art. We notice that Heidegger [25] also considers the sonic space, not only the tactile. Finally, in his introduction, Frampton [17] turns to the topic of tradition and innovation, also applicable to materials, since some, as is the case with reinforced concrete, were innovative materials but sometimes under extreme conditions performed worse than traditional ones such as wood. Tectonically significant was the iron skeleton, “ossiferous”, as Frampton [17] names it, of Labrouste’s Bibliothèque de Ste.-Geneviève, with its masonry and lightweight armature, to be continued by the theoretician of tectonics Viollet-le-Duc and by the reinforced concrete pioneer . Finally Frampton quotes passages of Viollet-le-Duc’s work, referring to the “truth” of the building in the material: “construction is the means, architecture is the result” [17], with which we come back to Heidegger’s “On the Origin of the Work of Art” [25] and the truth and to today’s approaches to conservation and authenticity (ex. the Nara document [28])“. In 1890, some seventeen years before Francois Hennebique’s decisive reinforced concrete patents of 1907, the engineer Paul Cottancin perfected his own reinforced masonry system known as ’ciment armé’[17]. Cottancin’s patent becomes obsolete in 1914; it required permanent brick formwork, instead of Hennebique’s temporary timber framework, another connection between reinforced concrete and timber as materials. In Cottancin’s system wire reinforcement acted in tension and cement infill in compression independently, thus avoiding a weakness persisting till today in the adherence between metal and concrete. The first to explain “the origin of the tectonic form in terms of the materials available, the structural systems employed, and the state of craft production” [17] was by Choisy, an engineer [29]. Although in “Vers une Architecture” [30] was inspired by Choisy’s isometric drawings, these represented better load bearing structure than skeletons, such as, for example, timber framework. Frampton deems Auguste Perret to be Choisy’s follower, but he also influenced the architects of the “machine age” from Le Corbusier to Louis Kahn. “Choisy seems to have anticipated reinforced concrete as the sole technique that would prove capable of overcoming the age-old schism and fusing into a single entity the two great lines of Western building culture” [17] (which are timber construction and masonry). In his discussion of the Germans, Frampton comes back to the duality of the ontological-representational and its synonyms (ex. core form and artistic form) which we saw at the beginning. For example, Schinkel’s “Das architektonische Lehrbuch” (the architectural manual) [31] “contains many examples of differently articulated structural assemblies, rendered in different materials. In the main, these sketches are ontological rather than representational in character, that is to say Sustainability 2020, 12, 5925 6 of 26 the tectonic system itself is emphasized rather than the cladding of its form” [17], i.e., the core form predominates over the art form. We might add to this that, in the 19th century, the perception of the artistic expression of illustrations, regarded today from a technical/engineering point of view, was different. Unlike the architects of the early 20th century, who looked for the best expression for a given material, Schinkel emphasized in this work the use of the best possible material for a given form, and highlighted the quality of craftsmanship and how the materials are joined together. Frampton returns to the analysis of Bötticher’s work and the examination of the ontological status of the structure and representational status of the ornament [17]: the representational is assimilated to the Greek and the ontological to the Gothic. On a personal note, the Greeks translated timber, which is suitable for the skeleton, into masonry, while in Gothic architecture the skeleton structure was built of masonry. A philosophical influence on Bötticher comes from Schopenhauer: “architecture could only express its essential form and significance through the dramatic interaction of support (pillar) and load” [17], arguing thus for sincerity in architecture (“beauty was [...] the explanation of mechanical concepts” [17]). Not only should the core form, a mechanical-statical necessity, be expressed as such, but the art form, ornament, or cladding, should likewise be expressed as a separate part. This expression was reflected in the Secession architecture of Otto Wagner, and those influenced by his language, for example the architect from Oradea József Vágo (Figure4). Bötticher argues for new materials, in this case iron, saying that stone had reached its apogee in the Gothic period, and that iron would be more suitable to cover large openings. A new material brings “in its train a new world of art-forms” [17]. The author sees that “the tectonic expressivity of such an unprecedented system will have to model its representational form on some kind of reinterpretation of the principles of Hellenic architecture. [...] anticipates the semiotic transformations of Jugendstil in its crystallizing phase, particularly [...] Otto Wagner” (The principles of the Hellenic and Germanic way of building [19]). In the Stoffwechsel-theory Semper [19] observes the transformation through mythical, originally tensile construction into petrified compressive forms (the Greeks’ timber in stone). The nomadic textile forms were transformed into a permanent material when bricks became “dressing”, which we can see also in connection with Deleuze’s smooth and striated space [32], when distinguishing between nomad and sedentary. Otto Wagner pushed Semper’s theory further: “a new style must depend of necessity on a new means of construction” [33]. Wagner was, according to Frampton, the heir of Schinkel, Bötticher and Semper. “New purposes must give birth to new methods of construction and by this reasoning also to new forms” [34], so a new Kunstform derives from a new “Werkform, as inorganically articulated structural invention” [35]. He applied Semper’s theory of dressing with the tiles and nails on the Postsparkasse. The chapters which follow in [17] are dedicated to the analysis of tectonics in the work of several architects: Frank Lloyd Wright (8 June 1867, Richland Center–9 April 1959, Phoenix) where he identifies the so-called “text-tile” tectonic, the reinforced concrete pioneer Auguste Perret (12 February 1874, Ixelles, Belgium–25 February 1954, Paris) (Figure5) and his contemporary (10 May 1873, –21 March 1932, Paris) and so-called “classical Rationalism”, Mies van der Rohe (27 March 1886, Aachen–17 August 1969, Chicago) and the Avant Garde, Louis Kahn (20 February/5 March 1901, Kuressaare, Estonia, Russian Kingdom–17 March 1974, New York) vis à vis Modernism, Jørn Utzon (9 April 1918, Copenhagen–29 November 2008, Helsingør) and the tectonic metaphor in trans-cultural form, and finally the joints designed by Carlo Scarpa (2 June 1906, Venice–28 November 1978, Sendai, Japan) in the late 20th century. The work of Carlo Scarpa and the interpretation in [18] is also touched thus in [17]. Sustainability 2020, 12, x FOR PEER REVIEW 7 of 27

Sustainability 2020, 12, 5925 7 of 26 Sustainability 2020, 12, x FOR PEER REVIEW 7 of 27

(a) (b)

Figure 4. Otto Wagner’s influence: (a) Postsparkasse, Vienna, architect Otto Wagner 1904–1906; (photo: M. Bostenaru, 2005); (b) Arkaden-bazár, Budapest, architect József Vágo, 1909; (photo: M. Bostenaru, 2003).

The chapters which follow in [17] are dedicated to the analysis of tectonics in the work of several architects: Frank Lloyd Wright (8 June 1867, Richland Center–9 April 1959, Phoenix) where he identifies the so-called “text-tile” tectonic, the reinforced concrete pioneer Auguste Perret (12 February 1874, Ixelles, Belgium–25 February 1954, Paris) (Figure 5) and his contemporary Henri Sauvage (10 May 1873, Rouen–21 March 1932, Paris) and so-called “classical Rationalism”, Mies van der Rohe (27 March 1886, Aachen–17 August 1969, Chicago) and the Avant Garde, Louis Kahn (20 February/5 March 1901, Kuressaa(a) re, Estonia, Russian Kingdom–17 (Marchb) 1974, New York) vis à vis Modernism, JørnUtzon (9 April 1918, Copenhagen–29 November 2008, Helsingør) and the tectonic Figure 4. OttoOtto Wagner’s Wagner’s influence: influence: (a (a) )Postsparkasse, Postsparkasse, Vienna, Vienna, architect architect Otto Otto Wagner Wagner 1904–1906; 1904–1906; metaphor(photo: in trans-culturalM. M. Bostenaru, Bostenaru, 2005);form, 2005); (and (bb)) Arkaden-bazár, Arkaden-baz finally the jointsár, Budapest, Budapest, designed architect architect by Carlo József József Scarpa Vágo, Vágo, (2 1909; June (photo:1906, Venice– M. M. 28 NovemberBostenaru, 1978, 2003). Sendai, Japan) in the late 20th century. The work of Carlo Scarpa and the interpretation in [18] is also touched thus in [17]. The chapters which follow in [17] are dedicated to the analysis of tectonics in the work of several architects: Frank Lloyd Wright (8 June 1867, Richland Center–9 April 1959, Phoenix) where he identifies the so-called “text-tile” tectonic, the reinforced concrete pioneer Auguste Perret (12 February 1874, Ixelles, Belgium–25 February 1954, Paris) (Figure 5) and his contemporary Henri Sauvage (10 May 1873, Rouen–21 March 1932, Paris) and so-called “classical Rationalism”, Mies van der Rohe (27 March 1886, Aachen–17 August 1969, Chicago) and the Avant Garde, Louis Kahn (20 February/5 March 1901, Kuressaare, Estonia, Russian Kingdom–17 March 1974, New York) vis à vis Modernism, JørnUtzon (9 April 1918, Copenhagen–29 November 2008, Helsingør) and the tectonic metaphor in trans-cultural form, and finally the joints designed by Carlo Scarpa (2 June 1906, Venice– 28 November 1978, Sendai, Japan) in the late 20th century. The work of Carlo Scarpa and the interpretation in [18] is also touched thus in [17].

(a) (b)

FigureFigure 5. 5. EarEarly ly use use of of reinforced reinforced concrete concrete with with Art Art Nouveau Nouveau reminiscences reminiscences in in Paris: Paris: (a (a) )Block Block of of flats flats onon Rue Rue Franklin, Franklin, architec architectt Auguste Auguste Perret Perret (1902–1904). (1902–1904). (b ()b Block) Block of of flats flats on on Rue Rue Vavin Vavin 26, 26, architect architect HenriHenri Sauvage Sauvage (photos: (photos: M. M. Bostenaru, Bostenaru, 2010). 2010).

2.2.2.2. Essays Essays In Italy (Torino, Mina [36]), Belgium (Henri van de Velde [37]), and Hungary (István Medgyaszay [38]), practicing architects were seeking a language for reinforced concrete. Erich Mendelsohn reflected on the use of concrete in the Einstein tower in , Germany, to the language developed for concrete by Henri van de Velde, as is evident in his letters [37]. The Einstein tower (Figure6a) is considered to express concrete in an appropriate shape, but it was mainly made of brick and(a) iron. This was also foreconomic reasons, iron being(b) a widely used material in industrialFigure 5. Ear Germany ly use of during reinforced that concrete time. Thiswith Art and Nouveau the whole reminiscences challenges in of Paris: restoration (a) Block areof flats written in Huseon Rue [39 ].Franklin, Challenges architec oft restoration Auguste Perret included (1902–1904). the thermal (b) Block bridges of flats of on iron Rue and Vavin concrete 26, architect not being coveredHenri by Sauvage sufficient (photos: brickwork. M. Bostenaru, A similar 2010). example of a dynamic form suitable for concrete is seen in Béla Lajta’s block of flats on Népszinház street (Figure6b), which is classified by Ákos Moravánszky 2.2. Essays Sustainability 2020, 12, x FOR PEER REVIEW 8 of 27

In Italy (Torino, Mina [36]), Belgium (Henri van de Velde [37]), and Hungary (István Medgyaszay [38]), practicing architects were seeking a language for reinforced concrete. Erich Mendelsohn reflected on the use of concrete in the Einstein tower in Potsdam, Germany, to the language developed for concrete by Henri van de Velde, as is evident in his letters [37]. The Einstein tower (Figure 6a) is considered to express concrete in an appropriate shape, but it was mainly made of brick and iron. This was also foreconomic reasons, iron being a widely used material in industrial

GermaSustainabilityny during2020, 12 ,that 5925 time. This and the whole challenges of restoration are written in Huse 8[39]. of 26 Challenges of restoration included the thermal bridges of iron and concrete not being covered by sufficient brickwork. A similar example of a dynamic form suitable for concrete is seen in Béla Lajta’s blockas neither of flats belonging on Népszinház to the Secession street (Figure nor to 6b), the which National is classified Romantic by style, Ákos but Moravánszky to “the new as language neither belongingof reinforced to the concrete” Secession [40 nor]. However, to the National a visit Romant on site revealsic style, thebut sameto “the structure new language as in the of casereinforced of the concrete”Einstein Tower. [40]. However, Lajta seems a visit to haveon site turned reveals to the reinforced same structure concrete as with in the the case Rózsavölgyi of the Einstein house, Tower. as we Lajtawill laterseems see. to have Van deturned Velde to saw reinforced a connection concrete between with the the Rózsavölgyi shape to be house, used for as concretewe will later and thatsee. Vanused de for Velde timber, saw and a connection this view wasbetween not unique.the shape The to be opinion used for was concrete shared and by the that Hungarian used for timber, István andMedgyaszay, this view whowas wasnot unique. a student The of opinion Otto Wagner, was shared and expressed by the Hunga his viewsrian bothIstván theoretically Medgyaszay, [38 ]who in a waslecture a student in Vienna of Otto and Wagner, practically, and in expressed the concept his of view thes theatre both theoretically in Veszprém, [38] Hungary. in a lecture In his in seminalVienna andbook practically, on tectonics, in the Kenneth concept Frampton of the theatre [17] gives in Vesz an exhaustiveprém, Hungary. explanation In his onsemi hownal reinforcedbook on tectonics, concrete Kshouldenneth be Fr includedampton [ among17] gives tensile an ex materialshaustive such expl asanation timber, on and how their reinforced petrified concrete versions should inherited be includedfrom the among Greeks, tensile which materials is the load such bearing as timber, masonry, and and their which petrified acts inversions compression. inherited The from simple the Greeks,differentiation which is in the skeleton load bearing structure masonry, and load and bearing which masonry acts in compression. is not enough, The since simple skeleton differentiation structures inwere skeleton made structure out of stone and during load bearing the Gothic masonry period. is not enough, since skeleton structures were made

(a) (b)

FigureFigure 6. The shapeshape ofof reinforced reinforced concrete. concrete. (a ()a ’Einstein) ’Einstein Tower’, Tower’, architect architect Erich Erich Mendelsohn Mendelsohn (1919–1921) (1919– 1921)(photo: (photo: M. Kau M.ff Kauffmann,mann, 2002), 2002), (b) Block (b) Block of flats of onflats N éonpszinh Népszinházáz street, street, Budapest, Budapest, architect architect Béla LajtaBéla Lajta(1911) (1911) (photo: (photo: M. Bostenaru, M. Bostenaru, 2006). 2006).

3.3. PracticeFollowing PracticeFollowing the the Essays Essays SomeSome works byby IstvIstvánán Medgyaszay Medgyaszay (23 (23 August August 1877 1877 inBudapest, in Budapest, then th Austria-Hungary–29en Austria-Hungary–29 April April1959 in 1959 Budapest, in Budapest, Hungary) Hungary) in Veszpr in Veszprémém and Balatonalm and Balatonalmádi,ádi, both in both Hungary, in Hungary, as well asas somewell as projects some projectspublished published 1902 and 1902 1903 and in ’Der 1903 Architekt’, in ’Der Architekt’ in Vienna,, inbefore Vienna, graduation, before gradua willtion, be presented will be presented to see the toconnections see the connections between theorybetween and theory practice. and practice. István Medgyaszay István Medgyaszay was a student was a student of Otto Wagnerof Otto Wagner (13 July (131841 July in Penzing1841 in Penzing by Vienna–11 by Vienna–11 April 1918 April in Vienna) 1918 in atVienna) the master at the school master ’Spezialschule school ’Spezialschule für moderne für moderneArchitektur’ Architektur’ (Special school (Special for school modern for architecture).Gotfried ).Gotfried Semper (29 NovemberSemper (29 1803 November in Hamburg, 1803 inGermany–15 Hamburg, Germany–15 May 1879 in Rome,May 1879 Italy) in Rome, separates Italy) out separates the construction out the construction according to according the principle to the of principlethe primitive of the hut. primitive The floor, hut. wallThe floor, and ceiling wall and typology ceiling typology generated generated Loos’ ’Raumplan’ Loos’ ’Raumplan’ (Adolf Loos (Adolf 10 December 1870 in Brno, then Austria-Hungary, today Czech Republic–23 August 1933 in Kalksburg by Vienna, Austria), but in the search for a technically advanced and artistically convincing style for reinforced concrete Wagner’s student István Medgyaszay went the furthest. He worked with Hennebique (25 April 1842 in Neuville-Saint-Vaast–20 March 1921 in Paris) in Paris (1907), but his architecture does not show the French influence and is fundamentally different from Auguste Perret’s (12 February 1874 in Ixelles, Belgium–25 February 1954 in Paris) ’Theatre of the Champs Elysees’ in Paris (1913) (Figure7), the later taken over from Henri van de Velde the theory of whom was introduced Sustainability 2020, 12, x FOR PEER REVIEW 9 of 27

Loos 10 December 1870 in Brno, then Austria-Hungary, today Czech Republic–23 August 1933 in Kalksburg by Vienna, Austria), but in the search for a technically advanced and artistically convincing style for reinforced concrete Wagner’s student István Medgyaszay went the furthest. He worked with Hennebique (25 April 1842 in Neuville-Saint-Vaast–20 March 1921 in Paris) in Paris (1907), but his architecture does not show the French influence and is fundamentally different from AugusteSustainability Perret’s2020, 12 ,(12 5925 February 1874 in Ixelles, Belgium–25 February 1954 in Paris) ’Theatre of9 ofthe 26 Champs Elysees’ in Paris (1913) (Figure 7), the later taken over from Henri van de Velde the theory of whom was introduced above. In the lecture “on the artistic solution of reinforced concrete construction”above. In the lecture[38], Medgyaszay “on the artistic expressed solution his of thou reinforcedghts about concrete the separation construction” between [38], Medgyaszay design and spaceexpressed limitation. his thoughts The structural about the elements separation of the between building design should and be designed space limitation. in accordance The structural with this application.elements of theThus, building Medgyaszay should emphasized be designed inthe accordance flat character with of this the application.horizontal separating Thus, Medgyaszay building elements.emphasized the flat character of the horizontal separating building elements.

FigureFigure 7. ’Theatre 7. ’Theatre of theof the Champs Champs Elysees’ Elysees’ (Paris, (Paris, 1913) 1913) architect architect Auguste Auguste Perret Perret (photo: (photo: M.Bostenaru, M.Bostenaru, 2010). 2010). The effort to explore the specific mechanical characteristics (resistance) of the new material ferro-concreteThe effort into explore order to the characterize specific mechanical and to find char anacteristics artistic expression (resistance) in of the the shapenew material language ferro- for concretereinforced in concreteorder to ischaracterize important forand architectural to find an artistic history. expression Medgyaszay in the also shape sees language the artistic for relationship reinforced concreteof reinforced is important concrete with for timber.architectural The new history. and important Medgyaszay aspects also of thesees theater the artistic in Veszpr relationshipém, Hungary of (1908)reinforced were concrete also formulated with timber. in theThe lecture. new and Medgyaszay important aspects was no of strangerthe theater to in the Veszprém, national style,Hungary but (1908)here his were design also transcendsformulated thein the Oriental lecture. character Medgyaszay of the was extremely no stranger logical to the and national honest style, construction, but here hisreflecting design his transcends view of the the artistic Oriental element: character the problemsof the extremely of the time logical were and more honest important construction, than the reflectingcreation of his an view architectural of the artistic style. element: the problems of the time were more important than the creationThe of Theatre an architectural in Veszpré style.m (Figure 8a) is a multi-purpose hall for a small town. It is situated in the formerThe Bishop’s Theatre garden, in Veszprém which (Figure is considerably 8a) is a multi-purp lower thanose the hall adjacent for a road.small Thetown. auditorium It is situated measures in the former20 16sqm Bishop’s [37], is garden, sloping andwhich balanced, is considerably being suitable lower for than transformation. the adjacent road. The auditorium × measuresThe theater20×16sqm space [37], is is covered sloping by and a double-shell balanced, being construction. suitable for The transformation. inner shell of the auditorium consists of reinforced concrete decorative grilles for air heating and is hung on a very thin barrel-shaped reinforced concrete structure between T sections of iron. The building was ‘air-conditioned’ with heating and thus the windows cannot be opened. The window construction consists of reinforced concrete bars with glued glass windows, a patented solution. The almost brutal-looking ceiling in the foyer is made of precast reinforced concrete, featuring concrete lattice-work, and decorative concrete structures with a bonded glass window determine the formal look of a cast concrete house, in a different manner from Mendelsohn’s ‘Einstein’ tower in Potsdam, Germany (1919–1921) and from Lajta’s building in Budapest (1911). Perforated reinforced concrete surfaces are typical of Medgyaszay’s approach to the material, and can also be seen in the Laczkó Dezs˝omuseum building in the same city (Figure8b), which is, however, less innovative. As highlighted in the lecture, this might derive from the timber approach, as we see in the church in Balatonalmádi (1930) (Figure8c). However, solutions were found for reinforced concrete, and we may see projects which are suitable for the new material from the period he spent studying in Vienna, as published in ’Der Architekt’ [41,42]. Sustainability 2020, 12, 5925 10 of 26 Sustainability 2020, 12, x FOR PEER REVIEW 10 of 27

(a) (b)

(c)

Figure 8. ArchitectureArchitecture of of IstvánMedgyaszay IstvánMedgyaszay ( (aa)) Theatre, Theatre, Veszprém Veszprém (1908) (Photo: M. M. Bostenaru, Bostenaru, 2006), 2006), (b) Reinforced concreteconcrete perforatedperforated detailsdetails at at the the Lack LackóDezsóDezs˝oMuseum,ő Museum, Veszpr Veszprémém (1912), (1912), (c )(c Church) Church in inBalatonalm Balatonalmádiádi (1930) (1930) (photos: (photos: M. M. Bostenaru, Bostenaru, 2011). 2011).

4. The Spread of the Hennebique’System The theater space is covered by a double-shell construction. The inner shell of the auditorium consistsAs wellof reinforced as considering concrete the decorative efforts made grilles to examine for air heating the philosophy and is hung of the on material, a very thin it is barrel- worth shapedstudying reinforced how it was concrete actually structure used technically. between T In sect theions patented of iron. drawing The building on the Hennebiquewas ‘air-conditioned’ system a withnetwork heating of primary and andthus secondary the windows reinforced cannot concrete be op beamsened. andThe joists window is visible. construction This is a characteristic consists of whichreinforced was concrete not kept inbars later with reinforced glued glass concrete windows, skeleton a patented constructions, solution. where the hierarchy of primary and secondaryThe almost was brutal-looking often mixed. ceiling The German in the foyer language is made diff oferentiates precast reinforced between this concrete, early reinforced featuring concrete andlattice-work, the later version,and decorative calling theconcrete first iron-concrete structures with (’Eisenbeton’) a bonded glass and window the later steel-determine concrete the (’Stahlbeton’),formal look of while a cast in concrete English forhouse, this earlyin a diff versionerent also manner ferro-concrete from Mendelsohn’s is used. In Hungarian ‘Einstein’ tower however in ’vasbeton’Potsdam, Germany is used for (1919–1921) both. In Romanian, and from Italian, Lajta’s andbuilding French, in theBudapest material (1911). is called in a similar way to ‘reinforcedPerforated concrete’, reinforced not di ffconcreteerentiating surfaces between are thetypical kind of of Medgyaszay’s reinforcement. approach to the material, and canHennebique’s also be seen headquarters in the Laczkó were Dezs in Brussels,ő museum and building from there in the the same system city spread (Figure8b), through which offices is, however,and contractors less innovative. throughout As Europe highlighted and beyond. in the Tablelecture,1 and this Figure might9 showderive the from location the timber of the examplesapproach, asof thewe spreadsee in consideredthe church inin thisBalatonalmádi paper. (1930) (Figure 8c). However, solutions were found for reinforced concrete, and we may see projects which are suitable for the new material from the period he spent studying in Vienna, as published in ’Der Architekt’ [41,42].

4. The Spread of the Hennebique’System As well as considering the efforts made to examine the philosophy of the material, it is worth studying how it was actually used technically. In the patented drawing on the Hennebique system a network of primary and secondary reinforced concrete beams and joists is visible. This is a characteristic which was not kept in later reinforced concrete skeleton constructions, where the hierarchy of primary and secondary was often mixed. The German language differentiates between this early reinforced concrete and the later version, calling the first iron-concrete (’Eisenbeton’) and the later steel- concrete (’Stahlbeton’), while in English for this early version also ferro-concrete is used. In Hungarian however ’vasbeton’ is used for both. In Romanian, Italian, and French, the Sustainability 2020, 12, 5925 11 of 26

Table 1. Studies considered.

Country Name of Work City Intervention Italy Palazzo della Borsa Genoa Restored Grand Hotel Miramare Genoa Restored Porto Antico Genoa Restored + extension Via XX Settembre Genoa Preserved as is Mercato Orientale Genoa Preserved as is Silos Genoa Call for tender Ponte del Risorgimento Rome Preserved as is Lingotto Torino Restored + extension Ponte Corso Italia Bari Need for restoration Romania Bulevardul Magheru Bucharest Red dot policy calling for restoration Athenée Palace Bucharest Transformed more times Block of flats on Frumoasă street Bucharest Preserved as is Water tower at Medicine faculty Bucharest Demolished

Water tower on S, tirbey domain Buftea near Bucharest Preserved as is Cernavodă Bridge Cernavodă Closed

Silos Constant, a Different suggestions for restoration

Casino Constant, a Call for tender

Mosque Carol I Constant, a Preserved as is

Silos Galat, i Preserved as are Silos Brăila Preserved as are Water tower Brăila Restored Moskovits Miksa Palace Oradea Restored Neglected, unlike other ones in the Water tower at CFR locomotive depot Timisoara , same city Hungary Arkaden-Basar Budapest Restored Building on Népszinház street Budapest Neglected Rózsavölgyi house Budapest Preserved as is Water tower on Margaret island Budapest Restored Water tower on Svábhegy Budapest Preserved as is Restored 1984–1988, functional Pet˝ofitheatre Veszprém adaptation keeping main character Laczkó Dezs˝omuseum Veszprém Restored in the 1980s Szent Imre church Balatonalmádi Preserved as is Water tower Siófok Restored Re˝okpalace Szeged Restored Water tower Szeged Restored Austria Loos house Vienna Preserved as is Church of Holy Spirit Vienna Preserved as is Postsparkasse Vienna Restored Portugal Luis Bandeira Bridge Rio Vouga Submerged to a dam Water tower Barreiro Call for tender Water tower, Penha de Franca Lisbon Preserved as is Faculty of Medicine, University of Lisbon Preserved as is Lisbon Latvia Water tower of Agenskalns Riga Preserved as is Water tower Ciekurkalnsˇ Riga Preserved as is Germany Bürgerparkviertel Darmstadt New development in historic site Einsteinturm Potsdam Restored ZKM Karlsruhe Restored + extension Speicher Altona Hamburg Restored + extension Egypt Baron Palace Cairo Subject of investigation from Vienna Israel Water tower Tel Aviv Restored Block of flats Rue Franklin Paris Preserved as is Théâtre des Champs-Élysées Paris Restored Block of flats Rue Vavin Paris Restored Bourg-la-Reine near Villa Hennebique Altered in time Paris Sustainability 2020, 12, x FOR PEER REVIEW 12 of 27

Austria Loos house Vienna Preserved as is Church of Holy Spirit Vienna Preserved as is Postsparkasse Vienna Restored Portugal Luis Bandeira Bridge Rio Vouga Submerged to a dam Water tower Barreiro Call for tender Water tower, Penha de Lisbon Preserved as is Franca Faculty of Medicine, Lisbon Preserved as is University of Lisbon Latvia Water tower of Agenskalns Riga Preserved as is Water tower Čiekurkalns Riga Preserved as is Germany Bürgerparkviertel Darmstadt New development in historic site Einsteinturm Potsdam Restored ZKM Karlsruhe Restored + extension Speicher Altona Hamburg Restored + extension Subject of investigation from Egypt Baron Palace Cairo Vienna Israel Water tower Tel Aviv Restored France Block of flats Rue Franklin Paris Preserved as is Théâtre des Champs- Paris Restored Élysées Block of flats Rue Vavin Paris Restored Bourg-la-Reine Villa Hennebique Altered in time Sustainability 2020, 12, 5925 near Paris 12 of 26

FigureFigure 9.9. Map ofof casecase studies studies mentioned mentioned in thisin paper.this paper. Full mapFull here:map https:here: //https://www.google.com/maps/www.google.com/maps/d/drive?stated/drive?state=%7B%22ids%22%3A%5B%221Z4YmchEPS4pQAUpzf=%7B%22ids%22%3A%5B%221Z4YmchEPS4pQAUpzf_ b0swQsNI8dtlg-%22%5D%2C%22action%22%3A%22open%22%2C%22userId%22%3A%_b0swQsNI8dtlg- 22103245202827861421792%22%7D&usp%22%5D%2C%22action%22%3A%22open%22%2C%22userId%22%3A%22103245202827861421792%=sharing. 22%7D&usp=sharing. 4.1. Early Reinforced Concrete in Italy 4.1. EarlyThe discussionReinforced Concrete starts with in Italy Italy, as it was already mentioned in the introduction. In Italy the Sustainability 2020, 12, x FOR PEER REVIEW 13 of 27 representativeThe discussion of the starts Hennebique with Italy, system as it was was Giovanni already mentioned Antonio Porcheddu in the introduction. (26 June 1860 In Italy Ittiri–17 the OctoberOctoberrepresentative 1937 Turin), of the whowho Hennebique waswas basedbased system in in Turin Turin was and and Gi wasovanni was active active Antonio all all over over Porcheddu Italy, Italy, especially especially (26 June in the 1860in norththe Ittiri–17 north [43]. [43].The The archive archive can can be consultedbe consulted on on request request [44 [44]]. The. The FIAT FIAT Lingotto Lingotto factoryfactory (1916–1923) (Figure (Figure 10)10) byby Giacomo Giacomo Matté Matté TruccoTrucco (30 (30 January January 1869 1869 in in Trivy–15 Trivy–15 May May 1934 1934 in inTurin) Turin) is isone one of ofthe the examples examples of industrialof industrial architecture architecture which which gained gained importance, importance, also on also account on account of contemporary of contemporary conversion conversion (1983– 2002)(1983–2002) by Renzo by Piano Renzo (14 Piano September (14 September 1937, Genoa) 1937, Genoa)and because and because of its integration of its integration in the 2006 in the Winter 2006 OlympicWinter Olympic Games. Games.However, However, it is Genoa it is Genoawhere a where boulevard a boulevard was traced was tracedat the turn-of-the-century at the turn-of-the-century with buildingswith buildings constructed constructed according according to Hennebique’s to Hennebique’s new system, new system, namely namelythe Via XX the Settembre Via XX Settembre (Figure 11).(Figure 11).

(a) (b)

Figure 10. FIATLingotto factory, today Polytechnic of Turin, Italy. (a) reinforced concrete Figureelements;( 10. FIATLingottob) additions in factory, the conversion today Polytechnic process. (photos: of Turin, M. Italy. Bostenaru, (a) reinforced 2018). concrete elements;(b) additions in the conversion process. (photos: M. Bostenaru, 2018).

Figure 11. Via XX Settembre Genoa, Italy, incl. Mercato Orientale (on the left), a Hennebique type intervention in Italy (photos: M. Bostenaru, 2012).

4.2. Romania In Bucharest, a boulevard similar to Via XX Settembre in Genoa, featuring early reinforced concrete constructions, but with a skeleton structure, unlike the Hennebique method, was completed in the interwar period in the Modernist style (Figure 12). The buildings on this boulevard were damaged in the 1940 and 1977 earthquakes, with partial and total collapse followed by the altering and replacement of the damaged buildings, losing much of the initial unity, and retrofitting today may further alter their appearance. Sustainability 2020, 12, x FOR PEER REVIEW 13 of 27

October 1937 Turin), who was based in Turin and was active all over Italy, especially in the north [43]. The archive can be consulted on request [44]. The FIAT Lingotto factory (1916–1923) (Figure 10) by Giacomo Matté Trucco (30 January 1869 in Trivy–15 May 1934 in Turin) is one of the examples of industrial architecture which gained importance, also on account of contemporary conversion (1983– 2002) by Renzo Piano (14 September 1937, Genoa) and because of its integration in the 2006 Winter Olympic Games. However, it is Genoa where a boulevard was traced at the turn-of-the-century with buildings constructed according to Hennebique’s new system, namely the Via XX Settembre (Figure 11).

(a)

(b)

SustainabilityFigure 10.2020 FIATLingotto, 12, 5925 factory, today Polytechnic of Turin, Italy. (a) reinforced concrete elements;(b)13 of 26 additions in the conversion process. (photos: M. Bostenaru, 2018).

Figure 11. Via XX Settembre Genoa, Italy, incl. Mercato Orientale (on the left), a Hennebique type Figureintervention 11. Via in XX Italy Settembre (photos: Genoa, M. Bostenaru, Italy, incl. 2012). Mercato Orientale (on the left), a Hennebique type intervention in Italy (photos: M. Bostenaru, 2012). Sustainability4.2. Romania 2020, 12, x FOR PEER REVIEW 14 of 27 4.2. Romania In Bucharest,Bucharest, a a boulevard boulevard similar similar to Viato Via XX SettembreXX Settembre in Genoa, in Genoa, featuring featuring early reinforced early reinforced concrete concreteconstructions, constructions, but with but a skeleton with a skeleton structure, stru unlikecture, theunlike Hennebique the Hennebique method, method, was completed was completed in the ininterwar the interwar period inperiod the Modernist in the Modernist style (Figure style 12 (Figure). The buildings 12). The onbuildings this boulevard on this wereboulevard damaged were in damagedthe 1940 and in the 1977 1940 earthquakes, and 1977 withearthquakes, partial and with total partial collapse and followed total collapse by the followed altering and by replacementthe altering andof the replacement damaged buildings,of the damaged losing buildings, much of the losing initial mu unity,ch of andthe retrofittinginitial unity, today and retrofitting may further today alter maytheir further appearance. alter their appearance.

Figure 12. Magheru boulevard in Bucharest with the bu buildingilding which was the Modernist manifesto (ARO—Asigurarea RomRomâneascânească—building by architectarchitect HoriaCreangHoriaCreangăă,, fromfrom 1929).1929). (photo: M. M. Bostenaru, 2002).

The firstfirst exampleexample of of early early reinforced reinforced concrete concre inte the in Hennebique the Hennebique system insystem Bucharest, in Bucharest, Romania, Romania,isis the Athen theée Palace Athenée (1910–1912) Palace(1910–1912) (Figure 13 ).(Figure The initial 13). architectureThe initial architecture design was donedesign by was the done architect by

theof French architect origin of French but born origin in Romania but born Daniel in Romania Renard Daniel (1871 inRenard Dragomire (1871s ,inti, Dragomire Romania–1936?)ști, Romania– and the 1936?)civil engineer and the Georgecivil engineer Constantinescu George Constantinescu (4 October 1881, (4 Craiova, October Romania–111881, Craiova, December Romania–11 1965, December Coniston,

1965,UK), aConiston, student ofUK), Anghel a student Saligny of Anghel (19 April Saligny 1854, (19S, erb Aprilănes, ti–171854, JuneȘerbă 1925,nești–17 Bucharest), June 1925, the Bucharest), renowned theengineer renowned of the engineer Cernavod ofă thebridge Cernavod (1890–1895),ă bridge the (1890–1895), longest at the the time longest in Europe. at the time Anghel in Europe. Saligny

Anghelalso employed Saligny reinforcedalso employed concrete reinforced in the silos concrete of Br ăinila the and silos Gala oft, i Br (1886)ăila and in the Gala Danubeți (1886) harbours, in the

Danubeshortly afterharbours, the Monier shortly patent,after the and Monier at the patent, silos inand Constan at the tsilos, a (1899 in Constan/1904–1909,ța (1899/1904–1909, in the later years in theemploying later years ’Holzcement’), employing ’Holzcement’), on the seaside, on the thelatter seaside, after the the latter plans after of the architect plans Petreof architect Antonescu, Petre

Antonescu,with neoclassical with neoclassical architecture. architecture. The silos of ConstanThe silost, a of are Constan listed asța monumentare listed as in monument Romania and in Romania were the andfirst were in pre-cast the first concrete. in pre-cast Anghel concrete. Saligny Anghel studied Saligny in Germany, studied where in Germany, the patents where of Monier the patents arrived of

Monier1884–1887 arrived [45]. The1884–1887 silos in Constan[45]. Thet, a silos were in also Constan subjectța of were recent also conservation subject of discussion,recent conservation for which discussion,Irina Băncescu for pursuedwhich Irina some Bă studiesncescu ofpursued intervention some andstudies conservation, of intervention including and also conservation, a view on including also a view on contemporary silos and harbours, for example the Hafen City in Hamburg by Possehl & Co., 1896, so at a close date but still in brick [46] which the author visited (Figure 14).The silos in Constanța can be compared to the situation of the Hennebique silos (1901) in Genoa, where engineers A. Carissimo, G. Crotti, and G. B. De Cristoforis, performed by Porcheddu in style. Since 2007, the silos in Genoa bear the label of “site of artistic interest” [47]. In fact, both studies on historic reinforced concrete on the Romanian seaside were performed in Italy and this highlights the connection to case studies there (Figure 15). The silos of Genoa first were subject of some graduation thesises at both at the University of Genoa and the Turin Politechnic. They are in state of abandon since 1980s, and there is a call for tender to restore them. They are neighboring the Genoa old harbor regenerated by Renzo Piano in 1988–2001, who also regenerated FIAT Lingotto. Daniel Renard is also the creator of another representative Art Nouveau building on the territory of the Old : the Casino in Constanța (1909) (Figure 16) [48]. The Casino is today in advanced state of deterioration, but finally after intense discussions (it was included in the seven most endangered by Europa Nostra in 2007 [49], steel and concrete corrosion in the few concrete elements being identified as some of the issues) for this emblematic building 2019 restoration works started. The engineer George Constantinescu also designed the structure for the first building in reinforced concrete in Romania (reinforced concrete was used for the cupola and the minaret), the Mosque in Constanța (1910–1913) (Figure 17), also with New-Romanian elements, architect Victor Sustainability 2020, 12, 5925 14 of 26 contemporary silos and harbours, for example the Hafen City in Hamburg by Possehl & Co., 1896, so at a close date but still in brick [46] which the author visited (Figure 14).The silos in Constant, a can be compared to the situation of the Hennebique silos (1901) in Genoa, where engineers A. Carissimo, G. Crotti, and G. B. De Cristoforis, performed by Porcheddu in Art Deco style. Since 2007, the silos in Genoa bear the label of “site of artistic interest” [47]. In fact, both studies on historic reinforced concrete on the Romanian seaside were performed in Italy and this highlights the connection to case studies there (Figure 15). The silos of Genoa first were subject of some graduation thesises at both at the University of Genoa and the Turin Politechnic. They are in state of abandon since 1980s, and there is a call for tender to restore them. They are neighboring the Genoa old harbor regenerated by Renzo Piano in 1988–2001, who also regenerated FIAT Lingotto. Daniel Renard is also the creator of another representative Art Nouveau building on the territory of the Old Kingdom of Romania: the Casino in

Constant, a (1909) (Figure 16)[48]. The Casino is today in advanced state of deterioration, but finally after intense discussions (it was included in the seven most endangered by Europa Nostra in 2007 [49], steel and concrete corrosion in the few concrete elements being identified as some of the issues) for this emblematic building 2019 restoration works started. The engineer George Constantinescu also designed the structure for the first building in reinforced concrete in Romania (reinforced concrete was used for the cupola and the minaret), the Mosque in Constant, a (1910–1913) (Figure 17), also with

New-Romanian elements, architect Victor S, tefănescu (14 March 1877–1950), designed after the model of the mosque in Konya, Turkey [50], and for the Casino. The facade of the Athenée Palace in Bucharest, Romania, had already been changed during the interwar period by a Modernist intervention related to the Italian Novecento style carried out by the architect Duiliu Marcu (25 March 1885 in Calafat, Romania–9 March 1966, Bucharest), in 1937 [51]. In addition, the Athenée Palace in Romania underwent a new restoration in the 21st century, aimed mainly at increasing its seismic performance, but also connected to its conversion into a Hilton hotel. Another student of was the engineer

Elie Radu (20 April 1853, Botos, ani–10 October 1931), who designed bridges, roads, and railways as well as some water works, including the water towers in Brăila (Figure 18) and Drobeta Turnu-Severin, both cities on the . The water tower in Brăila has been altered in the 1980s during Socialism, but after 2018 renovated with European funds, like the one in Drobeta Turnu-Severin. Anghel Saligny himself designed the water tower at S, tirbey palace, a mid-19th century palace of a Walachian prince in Buftea, near Bucharest in 1920 in reinforced concrete. It was less important in the curriculum of Saligny and not detailed in [45], but it is nevertheless listed as monument of national importance in Romania, while several water towers are listed as local importance monuments. On the territory of the Old Kingdom of Romania during the Art Nouveau period the ’New Romanian’ style was the new style introduced at the turn-of-the-century. This was inspired by the vernacular Romanian construction of the so-called “cula” (fortified housing in Muntenia) but also the cult architecture of the Brâncovenesc style, as promoted by the Medieval Voivod Constantin Brâncoveanu. It can be found in some monasteries or residences (Mogo¸soaia),but was also characteristic of some now-vanished monuments (the Vacăre¸stimonastery 1716–1736, demolished 1986 by the order of

Nicolae Ceaus, escu). Other Romanian architects such as Virginia Andreescu-Haret [52], argued during Communism as the first female architect in the world, nevertheless the first in Romania and the first in the world depending on criteria such as ’practicing after proper graduation’, adhered to this style despite staying in Italy for a while for study, before turning to modernism. An interesting aspect of Virginia Haret’s work is, however, the fact that the first block of flats in reinforced concrete in Romania, situated on Frumoasă street corner to Calea Victoriei (1924–1928) (Figure 19), has been attributed to her. This block of flats has a different style from both New-Romanian and Modernism, and is referred to as eclectic [53], so there is a debate about who actually created the building. Virginia Haret also planned industrial constructions in early reinforced concrete, such as a water tower in the courtyard of the former Faculty of Medicine (1927), which had New-Romanian architectural elements and was later demolished (Figure 20). Sustainability 2020, 12, 5925 15 of 26

SustainabilityIn Transylvania, 2020, 12, x FOR which PEER REVIEW was part of the Austro-Hungarian empire and not of the Romanian15 of Old 27 Kingdom, there are also examples of the Hennebique system, in Oradea (the Moskovits Miksa palace Șfromtefănescu 1904–1905, (14 March in the 1877–1950), Munich Secession designed style, after the the so-called model of Lilienstil, the mosque [54 ],in Figure Konya, 21 Turkey). TheSecession [50], and forstyle the shows Casino. close The connections facade of the to HungarianAthenée Palace architecture. in Bucharest, In the Romania, construction had of already the Moskovits been changed Miksa duringpalace the by Kinterwarálmán Rimperiodánoczy by a Modernist jr. (1892–1912) interven precasttion related iron concrete to the Italian slabs, Novecento so-called Hennebiquestyle carried outplates by [the55] architect have been Duiliu used Marcu for the (25 first March time 1885 in Oradea in Calafat, after Romania–9 the plans of March Professor 1966, of Bucharest), engineering in 1937Szilá rd[51]. Zielinszky In addition, (1 May the Athenée 1860 in M Palaceátészalka, in Romania Austro-Hungary–24 underwent a new April restoration 1924 in Budapest, in the 21 Hungary),st century, aimeda pioneer mainly of reinforced at increasing concrete its seismic in Hungary performance, who worked but also in France connected at Gustave to its conversion Eiffel and, after into knowinga Hilton hotel.the Hennebique Another student patents, of lobbied Anghel for Saligny these in was Hungary. the engineer The palace Elie hasRadu been (20 recently April 1853, restored, Botoș afterani–10 an Octoberextensive 1931), 3D scanning who designed campaign bridges, in 2016–2017.On roads, and therailways territory as ofwell Romania as some Zielinszky water works, constructed including the therailway water water towers tower in (DepoulBrăila (Figure CFR)in 18) 1905 and in Drobeta Timis, oara Turnu-Severi by the samen, contractors both cities as on the the tower Danube. in Szeged. The waterIn Timi towers, oara in there Bră areila has two been other altered twin water in the towers 1980s induring Iosefin Socialism, (1913–1914) but andafter Fabric 2018 renovated neighborhoods. with EuropeanFor the first, funds, designed like the by one Art in Nouveau Drobeta Turnu-Se architectverin. Lászlo Anghel Székely Saligny (3 August himself 1877 designed in Nagyszalonta, the water towerHungary–23 at Știrbey January palace, 1934 a mid-19th in Timis ,centuryoara, Romania), palace of ina Walachian 2019, a conversion prince in programBuftea, near was Bucharest announced in 1920with ain co reinforcedffee shop andconcrete. coffee It museum. was less Vimportantíztorony [in56 the] is acurriculum database of of water Saligny towers and onnot the detailed territory in [45],of Hungary, but it is nevertheless Romania, Slovakia, listed as which monument were of part national of the importance Austro-Hungarian in Romania, Empire while at several the time water they towerswere built. are listed as local importance monuments.

Figure 13. Athenee Palace afterafter thethe ModernistModernist changes changes by by architect architect Duiliu Duiliu Marcu, Marcu, Bucharest Bucharest (photo: (photo: M. M.Bostenaru, Bostenaru, 2011). 2011).

Figure 14. HafenCity in Hamburg (photo: M. M. Bostenaru, Bostenaru, 2012).

Sustainability 2020, 12, 5925 16 of 26 SustainabilitySustainability 2020 2020, ,12, 12, ,x, x xFOR FORFOR PEER PEERPEER REVIEW REVIEWREVIEW 1616 of of 27 27

(a(a) ) (b(b) )

FigureFigure 15. 15. Industrial IndustrialIndustrial architecture architecture architecture in in in reinforced reinforced reinforced concrete: concrete: concrete: ( a( (a)a )Silos) Silos Silos in in in Genova Genova Genova (1901) (1901) (1901) during during during restoration; restoration; restoration; (b(b) )old old harbor harbor with with Renzo Renzo Piano PianoPiano addition. addition.addition. (photos: (photos: M. M. M. Bostenaru, Bostenaru, Bostenaru, 2012). 2012). 2012).

Figure 16. Casino in Constanța, Romania, architect Daniel Renard (1909) (photo: A. Bălăceanu). FigureFigure 16. 16. Casino Casino in in Constan Constan Constantța,ț,a, Romania, Romania, architect architect Daniel Daniel Renard Renard (1909) (1909) (photo: (photo: A. A. B B ăălălceanu).ăceanu).

FigureFigure 17. 17. 17. Carol CarolCarol I IMosque IMosque Mosque in in inConstan Constan Constanța,ța, t,Romania a,Romania Romania (1910–1913), (1910–1913), (1910–1913), architect architect architect Victor Victor Victor Ș ȘteftefăS,ănescutefnescuănescu (photo: (photo: (photo: A. A. BBA.ăălăl Băceanu).ceanu).ălăceanu). Sustainability 2020, 12, x FOR PEER REVIEW 17 of 27

Sustainability 2020, 12, 5925 17 of 26

SustainabilityFigure 2020 18., 12Water, x FOR tower PEERin REVIEW Brăila, engineer (1912–1913) (photos: M. Bostenaru, 2013).18 of 27

Figure 18. Water tower in Brăila, engineer Elie Radu (1912–1913) (photos: M. Bostearu, 2013).

On the territory of the Old Kingdom of Romania during the Art Nouveau period the ’New Romanian’ style was the new style introduced at the turn-of-the-century. This was inspired by the vernacular Romanian construction of the so-called “cula” (fortified housing in Muntenia) but also the cult architecture of the Brâncovenesc style, as promoted by the Medieval Voivod Constantin Brâncoveanu. It can be found in some monasteries or residences (Mogoşoaia), but was also characteristic of some now-vanished monuments (the Vacăreşti monastery 1716–1736, demolished 1986 by the order of Nicolae Ceaușescu). Other Romanian architects such as Virginia Andreescu- Haret [52], argued during Communism as the first female architect in the world, nevertheless the first in Romania and the first in the world depending on criteria such as ’practicing after proper graduation’, adhered to this style despite staying in Italy for a while for study, before turning to modernism. An interesting aspect of Virginia Haret’s work is, however, the fact that the first block of flats in reinforced concrete in Romania, situated on Frumoasă street corner to Calea Victoriei (1924– 1928) (Figure 19), has been attributed to her. This block of flats has a different style from both New- (a) (b) Romanian and Modernism, and is referred to as eclectic [53], so there is a debate about who actually createdFigureFigure the 19. building.19.Block Block of of flatsVirginia flats on on Frumoas Frumoas Haretă street ăalso street 50–56planned 50–56 by by Virginia Virginiaindustrial Haret(1924–1928) Haret(1924–1928) constructions ((a (() photoa )in photo early and and ( breinforced )(b plan) concrete,drawingplan such drawing of as a modulea waterof a module of tower two of apartments, in two the apartments courtyard not the, not of corner the the corner former module: module: Faculty M. Bostenaru, M. Bostenaru,of Medicine 2011). 2011). (1927), which had New-Romanian architectural elements and was later demolished (Figure 20).

Figure 20. Water tower by Virginia Haret (Bucharest city archives).

In Transylvania, which was part of the Austro-Hungarian empire and not of the Romanian Old Kingdom, there are also examples of the Hennebique system, in Oradea (the Moskovits Miksa palace from 1904–1905, in the Munich Secession style, the so-called Lilienstil, [54], Figure 21). The Secession style shows close connections to Hungarian architecture. In the construction of the Moskovits Miksa palace by Kálmán Rimánoczy jr. (1892–1912) precast iron concrete slabs, so-called Hennebique plates [55] have been used for the first time in Oradea after the plans of Professor of engineering Szilárd Zielinszky (1 May 1860 in Mátészalka, Austro-Hungary–24 April 1924 in Budapest, Hungary), a pioneer of reinforced concrete in Hungary who worked in France at and, after knowing the Hennebique patents, lobbied for these in Hungary. The palace has been recently restored, after an extensive 3D scanning campaign in 2016–2017.On the territory of Romania Zielinszky constructed the railway water tower (Depoul CFR) in 1905 in Timișoara by the same contractors as the tower in Szeged. In Timișoara there are two other twin water towers in Iosefin (1913–1914) and Fabric neighborhoods. For the first, designed by Art Nouveau architect Lászlo Székely (3 August 1877 in Nagyszalonta, Hungary–23 January 1934 in Timișoara, Romania), in 2019, a conversion program was Sustainability 2020, 12, x FOR PEER REVIEW 18 of 27

(a) (b)

SustainabilityFigure2020 19., 12 Block, 5925 of flats on Frumoasă street 50–56 by Virginia Haret(1924–1928) ((a) photo and (b) 18 of 26 plan drawing of a module of two apartments, not the corner module: M. Bostenaru, 2011).

Sustainability 2020, 12, x FOR PEER REVIEW 19 of 27

announced with a coffee shop and coffee museum. Víztorony [56] is a database of water towers on

the territory of Hungary, Romania, Slovakia, which were part of the Austro-Hungarian Empire at the time they were built.FigureFigure 20. 20. WaterWater towertower by Virginia Haret Haret (Bucharest (Bucharest city city archives). archives).

In Transylvania, which was part of the Austro-Hungarian empire and not of the Romanian Old Kingdom, there are also examples of the Hennebique system, in Oradea (the Moskovits Miksa palace from 1904–1905, in the Munich Secession style, the so-called Lilienstil, [54], Figure 21). The Secession style shows close connections to Hungarian architecture. In the construction of the Moskovits Miksa palace by Kálmán Rimánoczy jr. (1892–1912) precast iron concrete slabs, so-called Hennebique plates [55] have been used for the first time in Oradea after the plans of Professor of engineering Szilárd Zielinszky (1 May 1860 in Mátészalka, Austro-Hungary–24 April 1924 in Budapest, Hungary), a pioneer of reinforced concrete in Hungary who worked in France at Gustave Eiffel and, after knowing the Hennebique patents, lobbied for these in Hungary. The palace has been recently restored, after an extensive 3D scanning campaign in 2016–2017.On the territory of Romania Zielinszky constructed the railway water tower (Depoul CFR) in 1905 in Timișoara by the same contractors as the tower in Szeged. In Timișoara there are two other twin water towers in Iosefin (1913–1914) and Fabric neighborhoods. For the first, designed by Art Nouveau architect Lászlo Székely (3 August 1877 in Nagyszalonta, Hungary–23 January 1934 in Timișoara, Romania), in 2019, a conversion program was FigureFigure 21. 21.Moskovits Moskovits Miksa Miksa Palace Palace (1904–1905),(1904–1905), architec architectt Kálmán Kálmá nRimánoczy Rimánoczy Jr., Jr.,Oradea Oradea before before restorationrestoration (photo: (photo: M. M. Bostenaru, Bostenaru, 2009). 2009).

UnlikeUnlike in the in the case case of Italy,of Italy, in in Romania Romania concrete concrete did not not spread spread wide wide as asearly early as the as Hennebique the Hennebique system, but spread widely instead suddenly during the interwar period, the potential of the material system, but spread widely instead suddenly during the interwar period, the potential of the material being insufficiently researched, especially given the earthquakes which occur here. Numerous beingbuildings insufficiently on the researched, Magheru Boulevard especially (Figure given 12) the colla earthquakespsed, rendering which the occur material here. vulnerable. Numerous Today, buildings on thehow Magheru to retrofit Boulevard them is being (Figure discussed 12) collapsed, and there is rendering some state thesupport material for this. vulnerable. Today, how to retrofit them is being discussed and there is some state support for this. 4.3. Hungary 4.3. Hungary Szilárd Zielinszky built a number of water towers in Hungary [55], the first one in Kőbánya in Szil1903,á rddemolished Zielinszky in 1968. built Some a number others of have water been towers refurbished, in Hungary for example [55], the the one first in oneSzeged in K˝ob (1904),ánya in 1903,which demolished has been in also 1968. strengthened Some others 2005–2006 have been[55]avoi refurbished,ding corrosion, for examplein frame of the the one rehabilitation in Szeged of (1904), whichthe has whole been open also place, strengthened and the one 2005–2006 on Margaret [55] avoidingIsland in Budapest corrosion, (1911) in frame UNESCO of the monument, rehabilitation of thearchitect whole Ray open Rezs place,ő Vilmos, and theconverted one on in Margaretan arts gallery Island since in 2012. Budapest In both (1911)cases architects UNESCO have monument, been involved in the refurbishment to make participative architecture out of concrete heritage. There is architect Ray Rezs˝oVilmos, converted in an arts gallery since 2012. In both cases architects have been one more water tower by Zielinszky on the Svábhegy in Budapest and other important ones in involved in the refurbishment to make participative architecture out of concrete heritage. There is one Szolnok, Hungary, and in Beočin, Serbia [55]. After the same technique as the tower on Margaret moreisland water the tower water by tower Zielinszky in Siófok on was the designed Svábhegy by in Árpád Budapest Gút (1877 and in other Kéthely–24 important May ones 1948 inin Szolnok,Tel Hungary,Aviv) andand inJen Beoˇcin,Serbiaő Gergely in1912 [ 55[57]]. After(Figure the 22). same The towe techniquer was altered as the 1935, tower and on then Margaret renovated island in the waterthe tower interior in Si inó fok1998. was In designed2010–2012, by theÁ exteriorrpád G úwast (1877 also inrenovated, Kéthely–24 now May being 1948 a complete in Tel Aviv) touristic and Jen˝o Gergelyhighlight in 1912 in [the57] Balaton (Figure lake 22). area. The Arpád tower Gút was later altered built 1935, a notable and (for then his renovated memories in[57]) the water interior tower in 1998. in Tel Aviv, Maze street (1924), with a menorah (a traditional Hanukah candelabrum) on the top (during the Festival of Lights), after he emigratedin Israel in 1921. The water tower is still staying. The water tower was renovated 2010–2016 [58]. Sustainability 2020, 12, 5925 19 of 26

SustainabilityIn 2010–2012, 2020 the, 12, exteriorx FOR PEER was REVIEW also renovated, now being a complete touristic highlight in the Balaton20 of 27 lake area. Arpád Gút later built a notable (for his memories [57]) water tower in Tel Aviv, Maze street (1924), with a menorah (a traditional Hanukah candelabrum) on the top (during the Festival of Lights), Sustainability 2020, 12, x FOR PEER REVIEW 20 of 27 after he emigratedin Israel in 1921. The water tower is still staying. The water tower was renovated 2010–2016 [58].

Figure 22. Watertower in Szeged, Hungary (photo: M. Bostenaru, 2009, before exterior renovation). Figure 22. Watertower in Siófok, Hungary (photo: M. Bostenaru, 2009, before exterior renovation). Art Nouveau construction following the French legacy is also very rarely to be found in the Figure 22. Watertower in Szeged, Hungary (photo: M. Bostenaru, 2009, before exterior renovation). neighboringArt Nouveau country construction of Hungary, following to which theTransylv Frenchania, legacy now ispart also of very Romania, rarely belonged to be found that intime, the theneighboring only notable country building of Hungary, being tothe which Palais Transylvania, Reők in Szeged now part(1907), of Romania,by Ede Magyar belonged (Figure that time, 23) (31 the Art Nouveau construction following the French legacy is also very rarely to be found in the Januaryonly notable 1877 building in Orosháza–5 being the May Palais 1912 Re˝okin in Szeged, Szeged Austria-Hungary), (1907), by Ede Magyar which (Figurerecently 23 (2007)) (31 January underwent 1877 neighboring country of Hungary, to which Transylvania, now part of Romania, belonged that time, restoration.in Orosháza–5 May 1912 in Szeged, Austria-Hungary), which recently (2007) underwent restoration. the only notable building being the Palais Reők in Szeged (1907), by Ede Magyar (Figure 23) (31 January 1877 in Orosháza–5 May 1912 in Szeged, Austria-Hungary), which recently (2007) underwent restoration.

FigureFigure 23. 23.Palais Palais Re˝ok,Szeged Reők, Szeged (1907), (1907), architect architect Ede Ede Magyar, Magyar, before before restoration restoration (photo: (photo: M. M. Bostenaru, Bostenaru, 1999). 1999). It is debatable whether the architecture of the National Romantic style, as it is called in Hungary Figure 23. Palais Reők, Szeged (1907), architect Ede Magyar, before restoration (photo: M. Bostenaru, and Latvia,It is debatable is to be whether considered the Artarchitecture Nouveau, of and the whetherNational the Romantic New-Romanian style, as it style is called belongs in Hungary to this. 1999). and Latvia,Reinforced is to be concrete, considered in Hennebique Art Nouveau, system, and whether is also documented the New-Romanian in the archives style belongs on the to works this. of BéReinforcedla Lajta (23 concrete, January in 1873 Hennebique in Óbuda, system, Austria-Hungary–12 is also documented October in the 1920 archives in Vienna, on the Austria) works of in It is debatable whether the architecture of the National Romantic style, as it is called in Hungary BélaBudapest Lajta [(2359], January the one mentioned1873 in Óbuda, with Austria-Hungary–12 the Népszinház street October building 1920 and in its Vienna, concrete Austria) language, in and Latvia, is to be considered Art Nouveau, and whether the New-Romanian style belongs to this. Budapesthighlighting [59], a compositionthe one mentioned with light with weightthrough the Népszinház skeleton street inbuilding the lower and storeys its concrete and heavy language, load Reinforced concrete, in Hennebique system, is also documented in the archives on the works of highlightingbearing masonry a composition in the upper with storey, light as weightthrough with Loos’ architecture skeleton in (Figure the lower 24). Thisstoreys is an and early heavy example load Béla Lajta (23 January 1873 in Óbuda, Austria-Hungary–12 October 1920 in Vienna, Austria) in bearingof Art Deco masonry at the in time the upper of Art storey, Nouveau, as with which Loos’ is toarchitecture be found also(Figure in Bucharest24). This is in an the early Santa example Elena Budapest [59], the one mentioned with the Népszinház street building and its concrete language, ofchurch Art Deco of the at Hungarian the time of community. Art Nouveau, Also which from Austria-Hungaryis to be found also (Slovenia), in Bucharest Jože Pleˇcnik(23in the Santa January Elena highlighting a composition with light weightthrough skeleton in the lower storeys and heavy load church of the Hungarian community. Also from Austria-Hungary (Slovenia), Jože Plečnik (23 bearing masonry in the upper storey, as with Loos’ architecture (Figure 24). This is an early example January 1872 in Ljubljana, Austria-Hungary–7 January 1957 Ljubljana), built the first church in of Art Deco at the time of Art Nouveau, which is to be found also in Bucharest in the Santa Elena reinforced concrete in Vienna (1910–1913), Austria (Figure 25), with its skeleton framework located church of the Hungarian community. Also from Austria-Hungary (Slovenia), Jože Plečnik (23 in the basement. This created a unique language which highlights the difference between a hall and January 1872 in Ljubljana, Austria-Hungary–7 January 1957 Ljubljana), built the first church in reinforced concrete in Vienna (1910–1913), Austria (Figure 25), with its skeleton framework located in the basement. This created a unique language which highlights the difference between a hall and Sustainability 2020, 12, 5925 20 of 26

1872 in Ljubljana, Austria-Hungary–7 January 1957 Ljubljana), built the first church in reinforced SustainabilitySustainabilityconcrete in 2020 2020 Vienna,, 1212,, xx FORFOR (1910–1913), PEERPEER REVIEWREVIEW Austria (Figure 25), with its skeleton framework located2121 in ofof the 2727 basement. This created a unique language which highlights the difference between a hall and a aastorey-wise storey-wisestorey-wise construction constructionconstruction [ [6].6[6].]. However, However,However, in inin his hishis hometown hometownhometown ofof Ljubljana,Ljubljana, Ple PleˇcnikpreferredPleččniknik preferredpreferred masonry masonry toto reinforcedreinforced concrete. concrete.

((aa)) ((bb))

FigureFigure 24. 24. ((aa)Loos)Loos) Loos househouse house atat at Michaelerplatz,Michaelerplatz, Michaelerplatz, ViennaVienna Vienna (photo:(photo: (photo: M.M. M. Bostenaru,Bostenaru, Bostenaru, 2006);2006); 2006); (( bb)))R RózsavölgyiRózsavölgyiózsavölgyi house,house, Budapest,Budapest, architectarchitect Béla BBélaéla Lajta Lajta (photo: (photo: M. M. Bostenaru,Bostenaru, 19971997 1997).

FigureFigureFigure 25. 25. 25.Church Church Church of theof of the the Holy Holy Holy Spirit Spirit Spirit (1910–1913), ( (1910–1913),1910–1913), Vienna, Vienna, Vienna, architect architect architect Jože Jože Jože Pleˇcnik,(Photo: Ple Pleččnik,nik, (Photo: (Photo: M. M. M. Bostenaru, Bostenaru, Bostenaru, 2005). 2005).2005). 4.4. Portugal and Latvia 4.4.4.4. PortugalPortugalAlso in and Portugal,and LatviaLatvia reinforced concrete was first employed in industrial architecture, where Bernardo Joaquim Moreira de Sá (1879–1919), later with the company Moreira de Sá & Malevez (MS&M), AlsoAlso inin Portugal,Portugal, reinforcedreinforced concreteconcrete waswas fifirstrst employedinemployedin industrialindustrial architecture,architecture, wherewhere were Hennebique’s agents [60,61]. Reinforced concrete for the Medicine School in Lisbon was tested BernardoBernardo JoaquimJoaquim MoreiraMoreira dede SáSá (1879–1919),(1879–1919), laterlater withwith thethe companycompany MoreiraMoreira dede SáSá && MalevezMalevez 1898 by Paul Cottancin himself [61]. Some notable constructions of them are bridges, of which not (MS&M),(MS&M), werewere Hennebique’sHennebique’s agentsagents [60,61].[60,61]. ReinforcReinforceded concreteconcrete forfor thethe MedicineMedicine SchoolSchool inin LisbonLisbon waswasall survived testedtested 18981898 time byby being PaulPaul demolishedCottancinCottancin himselfhimself in frame [61].[61]. of Some furtherSome notablenotable construction constructionsconstructions works on ofof thethemthem rivers areare bridges,bridges, (ex. a dam ofof whichwhichsubmerged notnot allall the survivedsurvived Luis Bandeira timetime beingbeing Bridge demolisheddemolished from 1906 inin/ 1907, frameframe the ofof oldestfurtherfurther in constructionconstruction concrete in works useworks in on Portugalon thethe riversrivers and (ex.(ex.one a ofa damdam the oldest submergedsubmerged in Europe thethe LuisLuis until BandeiraBandeira recently [Bridge62Bridge]). Other fromfrom industrial 1906/1907,1906/1907, buildings thethe oldestoldest by inin Hennebique’s concreteconcrete inin use agentsuse inin PortugalPortugalin Portugal andand are oneone water ofof the towersthe oldestoldest [60 ]: inin the EuropeEurope reservoirs untiluntil in recentlyrecently Lisbon Penha[62]).[62]). Other deOther Franca industrialindustrial district buildingsbuildings and Barreiro, byby Hennebique’sHennebique’sboth from 1907. agentsagents Lisbon inin featuresPortugalPortugal a are waterare waterwater museum towerstowers on [60]:[60]: four thethe historic reservoirsreservoirs sites which inin LisbonLisbon have PenhaPenha to do withdede FrancaFranca water, districtdistrictbut the and towerand Barreiro,Barreiro, is not part bothboth of fromfrom this. 1907. In1907. Barreiro, LisbonLisbon there featfeaturesures was a recentlya waterwater museum amuseum call for on artistson fourfour to historichistoric reuse the sitessites tower. whichwhich havehave toKratinsto dodo withwith and water,water, Tipane butbut [63 thethe] list towertower these isis industrial notnot partpart ofbuildingsof this.this. InIn asBarreiro,Barreiro, being part therethere of was itswas Art recentlyrecently Nouveau aa callcall architectural forfor artistsartists totoheritage, reusereuse thethe for tower.tower. example the Water tower of Agenskalns, on Alises 4 (1910) by Wilhelm Bockslaff (24 OctoberKratinsKratins 1858 andand in Riga, TipaneTipane Latvia–9 [63][63] listlist March thesethese 1945 industrialindustrial in Posen), buildingsbuildings along with asas beingbeing examples partpart of ofof National itsits ArtArt Romantic,NouveauNouveau architecturalarchitecturalclassified as suchheritage,heritage, also byforfor [ 64exampleexample] along the withthe WaterWater the Ciekurkalns towertower ofof Agenskalns,Agenskalns, (1912–1913) on wateron AlisesAlises tower. 44 (1910)(1910) Both waterbyby WilhelmWilhelm towers BockslaffBockslafffunctioned (24.(24. long OktoberOktober and are 18581858 still inin standing Riga,Riga, Latvia–9.Latvia–9. today. MärzMärz A discussion 19451945 inin Posen),Posen), on opportunities alongalong withwith of examplesexamples conversion ofof NationalNational of water Romantic,Romantic,towers, especially classifiedclassified in asas Romania, suchsuch alsoalso is byby given [64][64] inalongalong [65 ]. withwith The thethe contribution CiekurkalnsCiekurkalns highlights (1912–1913)(1912–1913) that waterwater few water tower.tower. towers BothBoth waterwater towerstowers functionedfunctioned longlong andand areare stillstill standingstanding today.Atoday.A discussiondiscussion onon opportunitiesopportunities ofof conversionconversion ofof waterwater towers,towers, especiallyespecially inin Romania,Romania, isis givengiven inin [65].[65]. TheThe contributioncontribution highlightshighlights thatthat fewfew waterwater towerstowers areare inin reinforcedreinforced concrete,concrete, likelike thosethose inin PortugalPortugal inin HennebiqueHennebique technique,technique, although,although, inin thisthis paper,paper, thethe oneone byby VirginiaVirginia Haret,Haret, notnot keptkept inin Bucharest,Bucharest, isis documenteddocumented inin FigureFigure 16.16. Sustainability 2020, 12, 5925 21 of 26 are in reinforced concrete, like those in Portugal in Hennebique technique, although, in this paper, the one by Virginia Haret, not kept in Bucharest, is documented in Figure 16. Also, the water tower on Angenskalns is discussed in [65]: the tower was raised and extended in 1937 and converted 1991–2010 for creative industries. Sustainability 2020, 12, x FOR PEER REVIEW 22 of 27 In his own house (1903, Bourg-la-Reine by Paris), Hennebique had used the volumetric shape of industrialAlso, the architecture, water tower includingon Angenskalns a water is discussed tower [ 65in ],[65]: an the architecture tower was raised in which and hisextended system in 1937 spread so much.and The converted villais 1991–2010 protected for as creative monument, industries. but it was renounced at some of the original functions, such as theIn his roof own garden, house (1903, while Bourg-la it is subdivided-Reine by intoParis), more Hennebique flats. had used the volumetric shape of industrial architecture, including a water tower [65], an architecture in which his system spread so 4.5.much. Britain The and villa Germany is protected as monument, but it was renounced at some of the original functions, such as the roof garden, while it is subdivided into more flats. In Britain and Germany Hennebique’s representatives were Mouchel and Züblin respectively [66]. The4.5. first Britain documented and Germany case of use of Hennebique’s system in Britain was Weaver’s mill in Swansea in 1897, followed by industrial, co-operative, railway, and silo buildings, while framed buildings In Britain and Germany Hennebique’s representatives were Mouchel and Züblin respectively in non-Hennebique’s[66]. The first documented system case appeared of use afterof Hennebique’s 1905 [67]. system Louis Gustavein Britain Mouchel was Weaver’s (11 January mill in 1852 in Cherbourg–27Swansea in 1897, May followed 1908 inby Cherbourg, industrial, co-ope France)rative, founded railway, with and the silo Hennebique buildings, while licence framed 1897 the companybuildings in Britonin non-Hennebique’s Ferry in the UK, system where appeared he spent after most 1905 [67]. of his Louis adult Gustave life. The Mouchel company (11 January Züblin was founded1852 in by Cherbourg–27 Swiss engineer May and 1908 pioneer in Cherbourg, of iron concrete France) founded construction with Eduardthe Hennebique Züblin (11licence March 1897 1850 in Castellammarethe company di in Stabia, Briton Italy–25Ferry in the November UK, where 1916 he inspent Zürich, most Switzerland).of his adult life. The The Technical company University Züblin of Viennawas infounded a team by lead Swiss by engineer Vittoria and Capresi pioneer analyzed of iron anconcrete example construction of the application Eduard Züblin of the (11 HennebiqueMarch system,1850 also in Castellammare using pre-cast di elements Stabia, Italy–25 made and November imported 1916 from in Zürich, Belgium: Switzerland). the Baron PalaceThe Technical in Cairo [68], University of Vienna in a team lead by Vittoria Capresi analyzed an example of the application of the where Hennebique constructed already in 1895 [62]. Hennebique system, also using pre-cast elements made and imported from Belgium: the Baron Palace In frame of the COST action TD1406 some case studies in “Innovation in intelligent management in Cairo [68], where Hennebique constructed already in 1895 [62]. of heritageIn frame buildings” of the COST were action studied TD1406 by the some author case ofstudies this paper,in “Innovation including in intelligent in Bucharest, management Romania and Karlsruhe,of heritage Germany. buildings” One were of studied the case by studies the author in Germanyof this paper, was including the building in Bucharest, of the Romania ZKM (Centre and for ArtsKarlsruhe, and Media), Germany. former One munitions of the case factory studies (1915–1918) in Germany now wasmuseum the building and of arts the universityZKM (Centre (Figure for 26). TheArts building and Media), is listed former as building munitions of special factory importance(1915–1918) now according museum to and the arts monument university law. (Figure Philipp 26). Jakob ManzThe (2 building December is listed 1861 as in building Kohlberg–2 of special January importance 1936 according in Stuttgart), to the an monument important law. architect Philipp Jakob of German industrialManz (2 architecture, December 1861 including in Kohlberg–2 textile January architecture, 1936 in and Stuttgart), also for an water important works architect [69], was of German the architect of theindustrial initial industrial architecture, building. including Manz textile used architectu here forre, theand firstalso timefor water a frame works construction [69], was the in architect Hennebique of the initial industrial building. Manz used here for the first time a frame construction in Hennebique technique [69]. The industry hall is the only one remaining from a larger industry area. In the last technique [69]. The industry hall is the only one remaining from a larger industry area. In the last decades a new function was searched for it. The conversion took place 1993–1997 [70]. Architects of decades a new function was searched for it. The conversion took place 1993–1997 [70]. Architects of the reconstructionthe reconstruction were were the the offi ceoffice Schweger Schweger and an Partner.d Partner. Parts Parts were were added added like like a cube a cube for for the the entrance. Theentrance. windows The were windows changed, were the changed, new cube the new is in cube steel, is and in steel, the oldand buildingthe old building is reinforced is reinforced concrete in Hennebiqueconcrete in system, Hennebique one ofsystem, the most one of advanced the most atadvanced its time. at Newits time. stairs New from stairs timber from timber and steel and were addedsteel in were the interior,added in asthe well interior, as passages as well as overpassages the atria.over the The atria. building The building is very is largevery large and and the onlythe one remainingonly one from remaining an industry from an areal industry and areal it was and di ffiit wascult difficult to use the to use atria. the Theatria. combination The combination of a of museum a andmuseum art school and is art very school good. is very good.

(a) (b)

FigureFigure 26. 26.ZKM ZKM museum museum and and artart universityuniversity buildin buildingg in inKarlsruhe Karlsruhe (1915–1918, (1915–1918, conversion conversion 1993–1997), 1993–1997), Germany.Germany. (Photos: (Photos: M. M. Bostenaru, Bostenaru, 2016).2016). (a): ZKM museum; (b): art university building.

5. Discussion and Conclusions Sustainability 2020, 12, 5925 22 of 26

5. Discussion and Conclusions Early reinforced concrete represents a stage in the development of a new material of importance for the history of construction. To date, this has been insufficiently researched, as it is rare that the history of architecture highlights the structure of a building. There is a need for research on this aspect, in order to be able to select constructions worth preserving as innovative landmarks in the structural system. This approach was called for at the f.i.b. (federation internationale du beton) Congress in Naples in 2006. The International Congress on Construction History, at its 6th edition in 2018 bridged this gap following initiatives in the UK and US, while in Germany architecture history chairs are often called “Baugeschichte” (construction history). The discipline of history of technology has a slightly different focus also regarding construction, and issues such as architecture and acoustics are touched, but not so much the relationship between structures and architecture as in the triennial conference series “Structures and architecture” in Guimarães, Portugal, mentioned in [11]. In Portugal also restoration includes architecture and civil engineering aspects in an exemplary synergy. In the meantime, the multidisciplinary approach between philosophy, architecture, and technical sciences (including sciences related to materials such as civil engineering but also chemistry) is important in order to fully assess the cultural significance one may attribute to material authenticity. Materials can be technically assessed and also produced, but it is necessary to understand their relationship to architectural shape, which is given by a philosophical view of the theory of architecture. Notable, in this analysis on concrete, is the relationship to timber as the architectural language had been developed, a relationship which is negated by today’s different seismic performance of reinforced concrete and timber. Art Nouveau was one of the many styles adopted by buildings with reinforced concrete structures. Others display Classical features, or were industrial buildings. But, common to both the development of reinforced concrete and the birth of Art Nouveau was the quest for a new style. Reinforced concrete called for a unique language across geographies. Apart of the housing or public buildings which display a style, the material has been used in numerous industrial buildings including water towers and also bridges. The house of Hennebique featured a water tower, as a symbol of the combination of residential and industrial architecture. For industrial buildings, with the economic shift today, challenges are different. For example, water towers were an architectural program which was in function only for a short time. In this case, in the decision of functional or material reuse, a new philosophy of the material, looking to the past, needs to be elaborated. Keeping the original material also contributes to the authenticity of the site, as architectural charters call for. In this sense, self-healing, as recently researched, is a promising technique for reinforced concrete as for natural materials such as stone. When reinforced concrete was introduced, it was considered a material to last forever. It generated great enthusiasm through the plastic capacity to fill any shape and through the ability to be industrially employed in large scale. This is shown also by the provided either industrial examples and/or with shapes expressing the philosophy behind the material. The search for a new language in architecture was combined with the search for a new language for the material. For this reason, it was employed at larger and larger scale. With time, durability proved much different. First only about a century displayed age alteration, second, where it was subjected to earthquakes, conflicts aroused between the flexibility it allowed in the floor plan and the necessities to resist horizontal loads. The plastic possibilities proved in contradiction with sustainability. Hence, today discussions on sustainability of concrete are different. Looking to the economic considerations of reuse against new construction is exceeding the frame of this paper, but thoughts are addressed today to economics of conservation, for example in the ICOMOS (International Council on Monuments and Sites) ISCEC (ICOMOS International Scientific Committee on Economics of Conservation) international scientific committee. Since many of these constructions are listed as monuments also because of their creative use of an early technology, furthering the impulses at the mentioned f.i.b. conference could be done in this direction. Reuse attempts shall consider the cultural, architectural, environmental value of the buildings in their surroundings, not just in case the building is listed as a monument, as in the European Charter of Sustainability 2020, 12, 5925 23 of 26 the Architectural Heritage from 1975, the European Architectural Year. Reuse is also reducing the energetic footprint which new constructions would generate. The examples provided in this paper show different creative ways of reuse for industrial and non-industrial buildings, including functional conversion, extension or replacement of parts related to functional conversion, or monument adequate restoration. In a few cases demolition could not be avoided, but some example reused the material through recycling. In the case of industrial buildings, such as silos, factories, and water towers, an additional challenge is given by the change of function compared to the time when they were built, and conversion to functions related to creative industries is done today in some cases. In the case of inner-city buildings instead, restoration of primarily the facades was done, accompanied sometimes by a change of functions as in Genoa. The tendencies are similar across Europe, in Eastern as in Western Europe already, which show lessons learned today 30 years after the fall of the Iron Curtain and return to the integration as at the time when these buildings were done and the architects travelled across Europe to learn the newest technologies from Paris and from Hennebique. The lessons reached countries neighboring Europe. The issue of local materials considered in today’s sustainability studies is colliding in the case of reinforced concrete, exactly with the philosophy of the material at the beginning of its employment, namely in international employment across countries and styles in Europe and beyond. The spirit of the time, at that moment, of enthusiasm of the industrial revolution was looking for new materials such as steel/iron, glass, and concrete. Today, we shall return at a mix of tradition and innovation which had early expressions at some of the architects of the time, who included local materials such as timber and stone in the language of Modernism in Romania (villas in Bucharest but mainly in Baltchik, Bulgaria by Henrietta Delavrancea-Gibory, a contemporary of Virginia Haret in Romania, but in a different style) or in Estonia (limestone Art Nouveau for example in central Tallinn, Estonia, another Baltic country, on Pikk street by Jaques Rosenbaum around 1909). This mix of tradition and innovation can be followed also in interventions on existing buildings, as the architecture of Carlo Scarpa in Veneto in Italy, in the attention to detail taught already at the end of the 20th century. The layering showing the material is an example on how it can be dealt with its authenticity following monument protection documents and is also a proof of respecting tectonic such as in the philosophy of the material concrete. There is plenty of inspiration in local architecture as a solution for these global challenges.

Funding: This research received no external funding. Acknowledgments: This work is based on a presentation held at the Art Nouveau Historical Lab 3 “Nature, Creativity and Production at the Time of Art Nouveau” held on the 19th of November 2011 in Milan by the Reseau Art Nouveau Network within the European project “Art Nouveau and Ecology”. The Romanian version before revision has been included in the doctorate and some insights regarding early reinforced concrete (not just in Hennebique system) are thus given in Bostenaru Dan, Maria, Dill, Alex and Gociman, Cristina Olga (2015) Digital architecture history of the first half of the 20th century in Europe, Editura Universitară “Ion Mincu”, Bucharest, available in the ICOMOS open archive. The author is grateful for the comments of three anonymous reviewers and of the academic editor which helped improving the paper a lot. Conflicts of Interest: The author declares no conflict of interest.

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