Mock-Up Presentation of the Gate Tower to the Hill Fort at Liptovská

Discussion Mock-up Presentation of the Gate Tower…

Fig. 2 The tower at the stage of a ﬁ nished rough construction in the summer of 2003. n Mock-up Presentation of the Gate Tower to the Hill Fort at Liptovská Mara Oto Makýš Department of Building Technology, Faculty of Civil Engineering, Slovak University of Technology, Bratislava, Slovakia *

l The author discusses the importance of including maintenance costs while planning an experimental construction based on the example of Lip- tov ská Mara.

Introduction Empire in Southwest Slovakia which Reconstruction of destroyed build- can be up to 2000 years old). All these ings or their parts is not uncommon reconstructions have a common base in Slovak building practise, especially – the building techniques originally in the area of monument renovation. developed by the Romans, which were It mostly concerns buildings in brick used not only on the territories and in and stone or their parts built within the period of the Roman Empire but far the last 1200 years (with exception of beyond both its territorial and temporal buildings from the Age of the Roman borders. With the exception of period

* Translation: J. Kateřina Dvořáková

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(medieval, modern) developments or experiments are primarily looking for local modifi cations it has fi rst funda- possible solutions and testing them. mentally changed during the 20th century. Th at means that the reconstruc- Future of an Experiment tions of destroyed ‘ancient’ structures Some of the recent experimental can be based on more or less identical constructions seem to concentrate only or analogous building solutions pre- on research, plan and execution of the served in other parts of Central, West- building. Th e question of further main- ern or Southern Europe (for example tenance has been neglected. Nearly every use of lime mortar). construction can have apart from the In recent years an increasing number research also an important and interest- of experimental constructions have ap- ing presentation function. Th is means peared – the building of structures from securing the further existence of the extinct cultures or from early phases constructions. It is therefore necessary of building development which are not to include the problem of maintenance well known and where the construction in the planning of the experiment. Th at and its details have to be based on local does not only infl uence the current so- archaeological research or archaeological lution of the construction but it might research of analogues. Th is concerns es- also instigate diff erent solutions of some pecially constructions built from organic unknown elements – maybe even solu- materials not only from pre- or protohis- tions closer to the original data. It is tory but also from the Middle Ages. Th e therefore necessary to determine straight problem of construction can be divided at the beginning if the building was built into several overlapping areas – ques- quickly or slowly, for short or long term tions, which have to be answered: use. It seems that most of the buildings l Design of the building in the past, as nowadays, were built for l Th e static schema extended use. Th e constructions from l Building materials organic materials are usually buildings l Solution of construction details of a high utility value and can survive l Used technology for a long time (for example preserved medieval roof timbers). Th e key lays in The entry information can only the preparation of building materials, par tially be specifi ed. Oft en most of the construction methods and mainly in above mentioned key information is continuous maintenance: missing. Use of analogous solutions based a) Th e composition and especially on other fi nds, oft en from large areas the proportion of tree species were dif- or parts of Europe does not necessarily ferent in the past. Th is also concerns supply suffi cient information. It must the quality of wood mass used, which also be pointed out that use of analogous is generally higher than it is today. solutions from later folk buildings might Th e environmental pollution today is be misleading. Construction details and substantially higher. In Slovak biotopes woodworking technology have devel- some of the species have been sup- oped – most preserved wooden cabins pressed (for example yew tree), some were built at the end of the 19th and be- others without natural enemies have ginning of the 20th centuries. Th erefore been introduced (for example acacia)

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and also there have appeared new pests tained before the start of the building. towards which Slovak biotopes are not It is clear that if the construction should resistant (for example the Domestic not disappear within few years regular Dry Rot Fungus Serpula lacrymans) upkeep is necessary. (Reinprech-Žák, 1998). c) Th e problems might be solved by, b) Modern methods solve the prob- for example, the use of acacia for posts lems of maintenance of wooden build- placed in ground, bandaging of the un- ings with the use of fundamentally dif- derground part of a post with bandages ferent building materials (concrete, steel, soaked with chemical preservatives, pres- plastic) which are unauthentic solutions, sure treatment of the underground parts, unsuitable for experimental construc- consistent placing of bottom beams on tions and besides which are not corner stones of suffi cient height, digging absolutely effective. circumferential channels, possibly even Therefore it is hidden drainage around the building to necessary to de- take rain water away quickly, placing of termine what drainage above the buildings or to divert way the future underground water and so on. Also for existence of the example covering straw or reed roofs with constructions thin nets protecting them against damage can be main- from birds and wind, regular airing of the building including the securing of necessary airing throughout the whole year. d) Th e placing of wooden beams into constructions – that means the construction details used – should be done in a way to prevent water penetration into the

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structure, to allow it respectively to run g) If a fungi infection is discovered the off and dry the organic material as fast action depends on its origin. If the infec- as possible (see placing of box-frames on tion came with the building wood then the corner stones). Even then it is not always infected part (and oft en also the adjacent possible to prevent the wooden structures parts) should have to be immediately from getting wet, especially the posts. and carefully removed and burnt at a safe Ways to repair wooden buildings with distance to stop the infection spreading. exchange of single damaged parts for If the infection is caused by neglect which new ones, without dismantling the whole results in a rise of the relative level of wood construction, have existed probably as humidity (for example insuffi cient airing, long as wooden structures and were part rise of the soil level up to the wooden of the constructors’ know-how. structure and so on) it is possible to try e) Regular maintenance (at least once (with airing, removing the soil and so a year – in the spring) means the clearing on) to transform the acute infection into away off grass, self-seeded trees and the a latent state, when the infection does not lowering soil deposits along the wooden develop any more (or minimally) and the constructions. It is not necessary to heat infected structure can survive without the the buildings because the drying eff ect replacing of parts for some time. is usually not proportional to the eff ort h) In any case it is necessary to take and expenses with the exception of one into account that aft er some time it would time drying of very damp constructions. be necessary to replace some elements of Otherwise regular airing is suffi cient. the building. Th e organic roof cover if it During maintenance it is also necessary is not continuously preserved by smoke, to pay attention to the condition of the has to be replaced under normal condi- roof and immediately repair any damage tions every 10 to 20 years, damp wooden which would allow water penetration. It beams in less than 10 to 15 years, earth is also useful to check the building during fast posts (depending on the preservative strong or long lasting rains which reliably use) in about 10 to 15 years. show any openings. i) Th ese ways of operating and main- f) Under condition where the hu- taining a building close to the original is midity level in the construction does not demanding on time, expenses and human cross 10%, or respectively 20% limits for power. Dependence on volunteers is not a more than 3 months, the structure has a solution, as it is possible to say from expe- chance of a long lifetime. Use of chemical rience that volunteer groups are mercu- preservatives is debatable because their rial (usually they endure the upkeep of a eff ect is on one hand time limited (it is structure for about 3-5 years). Th erefore necessary to renew it aft er certain time) the best solution is the founding of a and on the other technologically depend- professional service which looks aft er the ant (the most eff ective method is pressure operation and upkeep of the structure impregnation). At the same time their use or site or at least to affi liate the building is not suitable in spaces with a long term to an already existing professional body presence of people or animals (‘living’ (museum, local council) which then has open-air museums). On the other hand to guarantee the regular appropriating of their use for posts placed into ground is both human power and money necessary practically unavoidable. for the maintenance.

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Fig. 1 Condition of the tower in 2000. n Fig. 3 Condition of the tower in autumn 2003. n

Fig. 8 Horizontal strengthening of the tower Fig. 10 Putting on the covering under super- at ﬂ oor level. n vision. n

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j) Construction experiments are oft en on the Eastern terrace with a gate tower, done by enthusiasts. Either specialists, ar- a gate to the upper hill fort together with chaeologists, historians without technical fragments of walls, a wooden grubenhaus education or volunteers (usually students) and fi nally a medieval fort on the top of with various backgrounds. Th e advantag- the hill. All constructions fell under the es are low cost and enthusiasm together control of the Liptovské Museum which with a willingness to look for the most founded the fi rst archaeological open-air suitable construction and technological museum in Slovakia. solutions during the work without which During the earlier years of the run- the experiment probably cannot be car- ning of the open-air museum the prop- ried out. Th e disadvantages are the long erty manager (former management of time of execution and the need to devote the Liptovské Museum) did not respect time to work with volunteers. Th e use of its value and there was insuffi cient con- professional craft smen eliminates these tinuous maintenance of the site. Some disadvantages. On the other hand it brings structures were occasionally repaired, the danger of using modern solutions of rebuilt or added to but practically always construction details and techniques and on the initiative of the Archaeological In- usually much higher costs. stitute SAV and were limited by time and possibilities (Pieta 2002). Th is resulted in Construction of a mock-up extensive damage to the area, especially as an example of to the wooden structures which are most exposed to the weather. Gradually they a monument presentation had developed fungi infections, includ- Th e archaeological site on the Ha- ing infection with the Domestic Dry Rot vránok hill (Liptovská Mara – site 1) Fungus (Serpula lacrymans). In 2003 belongs among the most important sites of the museum management has changed the Púchovská culture (late La Tène – early and at the same time they succeeded in Roman Empire Period, the 2nd century securing a grant in co-operation with the BC – the 1st century AD) (Pieta 1996) not Archaeological Institute SAV, Faculty of only in Slovakia but in Central Europe. Civil Engineering and Faculty of Archi- Th e excavations have been taking place tecture both of the Slovak University of since 1965 under the leadership of PhDr Technology and the Institute of Monu- Karol Pieta, DrSc (Archaeological Institute ment Protection. Th e subject of the grant of the Slovak Academy of Science). From project ‘Ochrana a záchrana historických 1986 to 1992 the fi rst stage of the project of pamiatok na Slovensku ako integrálna gradual mock-up and experimental con- súčasť európskeho kultúrneho dedičstva struction of chosen elements in the area (koncepcia a realizácia)‘ / Protection took place with the aim of introducing and preservation of historical monu- visitors to the 3-D depiction of the men- ments in Slovakia as an integral part tioned era, within the landscape and on its of European cultural heritage (concept original site. Up to now there have been and execution) became the stabilisation constructed, using diff erent methods: a of the entrance area (gate tower and farmstead with the residential building adjacent wall – entrance to the sacrifi cial and several outbuildings, fragments of area) to the hill fort Liptovská Mara – site the defensive wall of the sacrifi cial area 1 – Havránok – the Eastern terrace.

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Th e preparation started with an exami- Th e presumed pyramidal roof was sug- nation of the grounds. On the basis of gested only with corner beams. its conclusions and hypotheses the sta- As material they used old electric bilisation project for the fi rst structure posts of unknown age which were origi- (gate tower) was prepared. nally machine shaped and pressure impregnated with an unknown chemical Initial conditions preservative. Th e exception was one of the The original structure of the gate posts which was made from freshly cut tower to the hill fort (sacrificial area) pine tree without chemical treatment. Th e from the east has not been preserved. Th e fl oor, wall and roof line were made from archaeological research (Pieta 1996) un- commonly available timber, also without covered a wall built from large fl at blocks any special treatment. Because it was only of sandstone, quarried probably on site a mock-up no special attention was paid in the form of large slabs, 5-15 cm thick. to the construction details and the joints Th e building blocks were overlapping (the were made with common nails of adequate original builders knew the basics of devel- sizes. In the places where rungs were at- oped wall building) connected only with tached recesses 5-7 cm deep were cut, clay (maybe clay mortar). At the gate area about 20 to 50 cm from each other. the wall was interrupted and the surface Th e lack of maintenance showed on was cobbled with middle size pebbles. Th e the tower construction with the decay presumed gate tower was preserved only of the pine post in the contact zone of in plan with four post-holes in the corners ground-air and its general weakening of an irregular trapezoid. Th e post-holes (during reconstruction it was possible to were originally about 60-90 cm deep. Th e break it with the pressure of one hand). placing of posts corresponds with recesses Part of the rungs was destroyed and in the preserved adjacent walls on both rot had developed in most of the joints sides. Based on the depth of the post-holes caused by the collecting of rain water. Th e it was presumed that the structure was a centres of the tops of the electric posts tower-like building, maybe up to three were also damaged – to about 0.3-0.5 m fl oors high. depth. Th e posts were cracked – some of During the already mentioned fi rst the cracks reached nearly 2/5 of the diam- stage of construction a tower-like struc- eter and were up to 1 m long. Two posts ture was built on the site of the original were damaged by woodpeckers – several entrance. As there was not enough rounded holes about 5-4 by 10-12 cm in information on its design it was built as size and about 5-7 cm deep. a mock-up (Pieta 1996). To preserve the natural character of the area, and recap- Outline of a solution turing the original design of the buildings Aft er assessing the situation on the it was decided to respect the original basis of the examination of the grounds building material – wood. Th e shape of the damage of the tower building was the structure was suggested only with the rated as in a state of disrepair (Znalecký lines of the load-bearing posts and beams štandart 1993) with rapid stabilisation at the height of the presumed fl oors. On necessary. Th erefore it was decided to the second fl oor there was constructed a carry out a general reconstruction of the fl oor and part of a wall up to 1.5 m high. tower structure. Because of the condition

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structure. Several years of experience has shown that to secure a continuous, uninterrupted and thorough maintenance of an uncovered wooden free standing skeleton structure exposed to the weather is impossible for many reasons (fi nancial, organisational, technical, human power etc). Without maintenance the lifespan of a substantial reconstruction would be again only several (7-10) years. To organize an expensive reconstruction bordering on a complete rebuild within such short intervals was assessed as being impossible. Th e solution had to be a type of construc- Fig. 7 Erecting a new post. n tion which would slow down the decay of the wooden material of the building. of the tower it was necessary to dismantle Conclusion 2: Th e gate tower will the entire structures and joints with the be constructed with roof and a circum- exception of three of the load-bearing ferential cover. (originally industrially treated) posts A combination of both points of which we decided to leave in their original view brought many important questions positions. Th anks to the scale of the work which were answered with following we have decided to reassess the original hypotheses. building design. Th e project was therefore determined by two main view points Problem 1: What shape and size – methodological and technical. should the tower be? Th e methodological point of view Solution: The tower, despite the concerned presentation. Th e experience above case, will continue to be a mock-up with the open-air museum confi rmed presentation as the information about its that the original idea that a 3-D presenta- design is minimal. In future it will not be tion of chosen structures would substan- presented only as the outline of a building tially increase the value of the area even but as a complete model of a possible tow- with a regard to the uncertainty of the er construction above the gate. Th e plan original design (it has not been possible of the tower is given. It will be expanded to recover it). Th e wooden construction only by the attaching of a cover. of the tower has fulfi lled its function as its Th e current elevation of the building (although only suggestive) shape enlivens will be preserved. Vertically the tower the whole of the sacrifi cial area and gives will be again divided into three fl oors. visitors the chance to imagine its design Th e fi rst fl oor will present the gateway, in its given era. the second a walk through fl oor on the Conclusion 1: Th e gate tower will level of the wall walk with an added de- be presented in 3-D form in the form fence function and the third guards and of a wooden construction. defensive position. Th e second fl oor will Th e technical point of view concerned be passable transversally (following the mostly the use and maintenance of the line of the walls), the third one will only

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be accessible by stairs. Th e height of the l Th e rotting tops of the posts fl oors while respecting technical restric- (centres) will be (according to tions (making use of recesses ready in the the scale of damage but at least posts, originally made for the attachment in the length of 0.5 m) cut of and of rungs) will be close to the current ty- replaced with new parts from pological agreement on ancient wooden impregnated wooden posts. Th ey fortifi cations in Europe. Th is means that will be joined by overlapping (to the height of the gateway will be about 3.5 at least 0.5 m length) while the cut m (height of a rider with a spear pointing surfaces will be at right angles upwards), the second floor about 3 m on both sides. Th e joint will be (standing warrior with a spear) and the strengthened with adhesive (Duvi- third fl oor (including the open roof space) lax) and nails (at least 2300 mm again about 3 m. nails, hammered towards each other at angle of at least 30°). Problem 2: In what way should the construction details, especially the Problem 3: In what way will be the joints be made? protection of the building secured? Solution: Because of the chosen Solution: Th e protection will be given method of a mock-up the construction mostly by means of the construction (Žák, details and joints will not be a recon- Reinprech 1998) in such a way that it: struction of an ancient building but l Minimises the possibility of rain openly admit to modern technology. Th e water getting into details and joints details will be therefore in the fi rst place l Secures as fast a fl ow off the as resistant as possible to weathering and structure as possible vandals. It was decided to use nails with l Secures as fast drying as possible possible minor adjustment of timber to of leaked or blown in water. improve the strength of the joint (fl atten- ing of surfaces) and to avoid any complex The main load-bearing construc- carpentry joints. tion (rough structure from vertical and Because of the scale of the damage to horizontal elements) will be built from the current structure only three (origi- industrially impregnated old electric posts, nally electric, pressure impregnated) which show elsewhere at the grounds (in posts will be left ; the rest will be replaced the same conditions) a very good state with new elements. Th e posts will be of preservation. Th e casing (roof, walls) repaired in the following fashion: and fl oor will be done in such a way as to l Th e biggest cracks and wood- allow the dismantling and replacement peckers’ holes will be plated (with of them in future without the necessity to thin lamellas from the waste from dismantle the main tower structure. At the other parts of the building of same time they will be made from cheaper impregnated posts, glued with wooden material (planks, split logs) so exterior adhesive Duvilax) that the cost of their renewal is as low as l Th e nests of decay at the joints possible. Th e parts exposed to weather with rungs will be cleaned back to (especially the roof) will be treated with the healthy wood and plated (see chemical preservatives. The posts will cracks and woodpeckers’ holes) be placed in ground using concrete (this

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method has been shown in other parts Estimated time of the area to increase the lifespan of the of reconstruction: wooden posts) with stone collars at surface Th e reconstruction can be carried level to blend in with the surrounding cob- out only from spring to autumn (ap- bling. Th e structure will be strengthened proximately April – October). Because at every vertical and horizontal plane with of the untested nature of the work and triangle and cross ties. Th e joints will be the participation of University students secured with nails. it is not possible to determine an obliga- tory time-table but it will be necessary Choice of material, tools to organize the work accordingly to the and workers situation on the building site. According to the scale and character of the work it Building material: is possible to estimate it will be fi nished l A fresh spruce trunk about 12 m within two seasons. long, 30 cm diameter on the thicker and 20 cm on the thinner ends to Execution replace one of the load-bearing posts l Old impregnated electric pylons of the reconstruction to make beams and crossbeams On the basis of these hypotheses and at least 4 m long, about 16-19 cm conclusions the project of the tower re- in diameter construction was prepared and the work l Round spruce timbers at least 4 m started in the summer of 2003. Th e work long, about 14-17 cm in diameter was carried out by the technicians from to strengthen the structure the Archaeological Institute and students l Split spruce logs at least 4 m long, from the Faculty of Civil Engineering about 12-16 cm in diameter for the and other Slovak and Czech Universities circumferential cover, staircase and together with the civic association Strom strengthening l Round spruce timbers, at least 4 m života. Building material was provided long, 8-16 cm in diameter for fl oors, by Liptovské Museum. Supervision was strengthening and roof beams provided by the author and PhDr Karol l Spruce planks, at least 4 m long, Pieta DrSc. Static scheme was consulted 2 cm thick for roof covering by ing Vladimír Kohút. l Spruce planks, at least 0.5 m long, During the work several problems 5 cm thick for stairs occurred. It was necessary to solve them l Further there will be used cement, on the spot. Th e experience of prepara- quarried sand, water, exterior adhe- tion and execution of an unusual recon- sive Duvilax and steel nails struction of an unusual building carried 150 – 300 mm long. out in an unusual way can be rounded up as follows: Workers: a) Within the given time it was shown Two specialised supervisors, one to be impossible to obtain and bring to qualifi ed building manger, two trained the site of the hill fort a fourth industrially technicians or craftsmen, 2-4 trained impregnated electric pylon more than assistants, 10-15 workers for preparation 10 m long – therefore we had to use a and transport of the building material. freshly cut spruce instead

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b) Th e original setting in concrete the natural line of the wall walk while of the other three main posts proved their width (about 70 cm) is a compro- to be in a very good condition and the mise between the need for as narrow an condition of wood in the contact zone opening as possible for defensive reasons ground-air was, despite long term use, and a wide opening for a comfortable and satisfactory – therefore the fourth post fast run through was also set in concrete. c) Th e setting of the new post into Conclusions the original hole had to be reversible During the summer and autumn of – therefore blocks of sandstone were 2003 and the spring of 2004 we have man- embedded into the concrete. If necessary aged to carry out most of the building con- it will be possible to break these and pick nected with the reconstruction of the gate the concrete out in pieces. tower on the Eastern terrace of Liptovská d) In two of the original posts (chemi- Mara 1. Some work remained (because cally treated!) woodpeckers made several of problems with obtaining wood) for the deep holes which weakened locally their summer of 2004. Aft er assessing the fi rst load-bearing capacity – the post were stage of the project we are preparing the therefore reinforced with lamellas completion of the space around the gate a) In place of many of the original with the constructing of adjoining parts joints of posts with rungs, decay had of the original defensive wall. Th e lower started – the damaged wood was therefore part of the wall was built in stone. During completely removed and the resulting the original project at the beginning of recesses again reinforced with lamellas the 1990ies it had not been completed up f) Th e centres of the tops of the posts to the uncovered height. Th e upper part started to rot ( up to 0.5 m) in the direc- of the wall was a wooden superstructure tion of the fi bres – we therefore cut off partly supported by posts. A substantial the ends and replaced them with new problem seems to be the active slope healthy wood, joined to the old posts by movement which permanently endangers overlapping the Eastern terrace of the hill fort which g) All fl oors were both in the hori- will have to be stabilised. As slope move- zontal and vertical planes made thor- ment is common in the Carpathians and oughly draught proof endangers also other monuments it will h) Th e slots on the second fl oor were have to be treated in an effective and narrowed to about 15 cm (the tested cheap way. minimum width necessary for the use of a bow and at the same time maximum Sources protection for the bowman) at 80 cm Th e reconstruction project utilises above the fl oor (tested maximum height designs prepared by ing arch Jozef Salus to allow to shoot at the space immediately provided by employees of the Archaeo- in front of the gate) logical Institute SAV in Nitra PhDr Karol i) Th e slots were placed in both op- Pieta DrSc and Štefan Hric. Th e designs posite walls to allow for shooting both were prepared in 1992 on the request outside and inside the hill fort from the building provider – Liptovské j) The door openings on the first Museum in Ružomberok and Archaeo- fl oor were placed at an angle to follow logical Institute SAV in Nitra.

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Bibliography Ashurst, J. – Ashurst, N.: Practical Building Conser vation. Vol. 5. Wood, Glass and Resins, English Heritage Technical Handbook, Gower Technical Press, Hants 1989. Beier, J. – Týn, Z.: Ochrana dřeva. Praha: Grada Pub lishing, 1996. Kohout J., Tobek A., Müller P.: Tesařství, Grada Pub lishing, Praha, 1996. kolektív autorov: (Re)konstrukce a experiment v archeo logii, zborník 3/2002, Společnost experimentální archeologie, Hradec Králové, 2002. Makýš, O.: Rekonštrukcie stavieb – technológia. Jaga Group, Bratislava, 2000. Pieta, K.: 10 rokov archeologického múzea v prírode v Lip tovskej Mare, In: (Re)konstrukce a experi ment v archeologii, No. 3/2002, Společnost experi mentální archeologie, Hradec Králové, 2002. Pieta, K.: Liptovská Mara – včasnohistorické centrum severného Slovenska, AÚ SAV, Nitra, 1996. Znalecký štandard. Bratislava: TSÚS, 1993. Žák, J. – Reinprecht, L.: Ochrana dřeva ve stavbě. Praha: ABF/Arch, 1998.

Fig. 4 Cleared and ﬁ lled in area of rot at the joint of a post and rung. n Fig. 5 Extension of the damaged ends of posts with overlapping joint. n Fig. 6 Reversible ﬁ tting of a post into concrete. n Summary Die Modelldarstellung des Torturms der Höhenburg von Liptovská Mara (Slowakei) in Originalgröße

Viele der gegenwärtig errichteten experimentalarchäologischen Konstruktionen scheinen ihren themati- schen Schwerpunkt im Bereich von Forschung, Planung und Aufb au des jeweiligen Gebäudes zu setzen. Dagegen kann beinahe jede Konstruktion – abgesehen vom Wert für die Forschung - eine bedeutende darstellende Funktion haben. Dies bedeutet, dass die zukünft ige Existenz der Bauten zu gewährleisten ist. Es ist deshalb notwendig, das Problem der Instandhaltung bei der Planung eines Experiments zu berücksichtigen. Der archäologische Fundplatz auf der Anhöhe von Havránok (Liptovská Mara – I) gehört zu den bedeutendsten Fundstellen in der Slowakei. Ein Projekt, bei dem in verschiedenen Abstufungen Modellbauten in Originalgröße und experimentalarchäologische Konstruktionen von ausgewählten Elementen des Gebiets errichtet wurden, konnte zwi- schen 1986 und 1992 durchgeführt werden - vor allem mit dem Ziel, die Besucher mit 3-D-Darstellungen vertraut zu machen. Mit unterschiedlichen Methoden wurden dabei folgende Objekte erbaut: Ein bäuerliches Gehöft mit Wohn- haus und diversen Außenanlagen, Teile des Verteidigungswalls mit einem Torturm, ein Tor zur oberen Höhenburg mit Abschnitten des zugehörigen Walls, ein aus Holz erbautes Grubenhaus und eine mittelalterliche Befestigung auf der Kuppe der Anhöhe. Der Torturm wurde als Modell in Originalgröße errichtet, da keine ausreichenden Informa-

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tionen über sein Aussehen vorhanden waren. Die vermutliche Form der Anlage konnte lediglich auf Grundlage der Pfostenreihen der tragenden Pfosten und der Balken in der Höhe der vermuteten Geschosse ermittelt werden. Das Obergeschoss wurde dabei als Geschossboden und als Teil des Walls in einer Höhe von bis zu 1,5 m aufgeführt. Das pyramidenförmige Dach war lediglich auf Grundlage der Eckbalken zu vermuten. Während der ersten Jahre waren die Instandhaltungsarbeiten für die Anlage nicht ausreichend, so dass es zu einem langsamen Verfall kam. Die fachliche Bewertung der Situation im Jahre 2003 erbrachte die Einschät- zung, dass der Turmbau eine sofortige Stabilisierung benötigte. Daraufh in wurde entschieden, dass der Turm vollständig rekonstruiert werden sollte. Die Erfahrungen bestätigten, dass die ursprüngliche Idee, eine 3-D-Darstellung ausgewählter Befunde würde den Wert des Geländes wesentlich steigern, korrekt gewesen ist. Mehrere Jahre an praktischen Kenntnissen haben darüber hinaus gezeigt, dass eine kontinuierliche, ununterbrochene und gründliche Instandhaltung einer ungeschützten, freistehenden, “skelettartigen” Struktur aus Holz, die dem Wetter dauerhaft ausgesetzt ist, aus verschiedenen Gründen (z. B. fi nanzieller, organisatorischer und technischer Art) nicht möglich ist. Ein Schutz muss vor allem durch ein entsprechendes äußeres Gehäuse und durch eine entsprechende Bauweise gegeben werden. Trotz der Ergänzungen wird der Turm eine Modelldarstellung in Originalgröße bleiben, da die Kenntnisse über das Aussehen nur minimal sind. In Zukunft wird er jedoch nicht nur als Umriss eines Gebäudes, sondern als ein vollständiges Modell einer möglicherweise auf diese Art gestalteten Turmanlage über dem Tor aufgeführt werden. Die grundlegende tragende Konstruktion wird aus alten, industriell gefertigten und imprägnierten Pfosten, die ehemals Elektroleitungen trugen, erbaut; diese Pfosten haben eine sehr gute Haltbarkeit im Boden. Die Errichtung des Gehäuses und des Bodens wird auf eine solche Weise durchgeführt, dass ein zukünft iges Auseinandernehmen und Ersetzen dieser Teile auch ohne den vollständigen Abbau der Anlage des Hauptturmes möglich ist. Bauteile, die dem Wetter ausgesetzt sind, werden mit chemischen Konservierungsmitteln behandelt. Die Pfosten werden im Boden mit Beton eingesetzt und an der Oberfl äche mit Ringen aus Steinen umfasst, damit sich der Einbau der Pfosten von ihrem Aussehen her gut in das umgebende Pfl aster aus Steinen einpasst. Die Anlage wird an jeder vertikalen und horizontalen Ebene mit Dreiecks- und Kreuzverbindungen stabilisiert. Die Verbindungen werden mit Nägeln abgesichert.

Présentation modèle de la porte ďentrée du village fortifi é de Liptovská Mara

La plupart des expérimentations récentes de reconstitutions se sont concentrées sur la recherche, ľorganisation et la réalisation. Or, presque chaque reconstitution peut remplir encore une grande fonction pédagogique et non seulement celle scientifi que. Mais cela exige ďassurer un bon état de la construction. Aussi dès le début, il est nécessaire de penser au problème des travaux ďentretien. Le site archéologique sur la butte de Havránok (Liptovská Mara - I) compte pour ľun des plus importants en République slovaque. Entre 1986 et 1992, on y a réalisé le projet de la reconstitution progressive, modèle et expé- rimentale des éléments choisis du site. Ce projet a eu pour but de présenter ce site aux visiteurs à trois dimensions. En appliquant diff érentes méthodes, on a reconstitué une ferme avec un habitat et des bâtiments ďexploitations, une partie de fortifi cation avec la porte ďentrée, la porte donnante sur la partie supérieure du lieu fortifi é avec ľenceinte contigüe, un habitat enterré et un châtelet médieval sur le sommet de la butte. Comme on n’a pas disposé d’assez de données, la porte ďentrée n’est qu’une construction modèle hypothétique. Sa forme a été marqué par les lignes des poteaux porteurs et des poutres posées aux niveaux des étages. Au deuxième étage on a construit le plancher et un mur jusqu’à la hauteur de 1,5 m. Le toit à deux versants a été indiqué par les poutres aux coins. Au début on ne s’est pas assez occupé de ces constructions à Liptovská Mara qui commençaient à se délabrer. En 2003 ľétat de la tour a été critique ce qui nécessitait une reconstruction immédiate. Ľexpérience a prouvé la justesse de ľidée de départ à savoir celle que la présentation des structures choisies à trois dimensions fera valoir le site. Les expériences ont aussi mis en évidence qu’un entretien continu et soigneux de la construction solitaire en bois n’est pas réel pour plusieurs raisons (fi nancières, organiques, techniques etc.). En eff et, la construction doit être préservée tout ďabord par un mur et aussi par la manière de réalisation. La tour garde son caractère de modèle car on dispose toujours du minimum de données sur son aspect. Néanmoins elle ne sera plus présentée sous les contoures, mais comme modèle ďune tour hypothétique. Les éléments porteurs de fonds seront réalisés en poteaux imprégnés de télécommunication qui ont déjà prouvé une très bonne résistence sur le site. Les murs et le plancher seront construits de manière à pouvoir être remplacés sans démateler la construction. Les éléments exposés aux intempéries seront imprégnés. Les poteaux seront plantés dans du béton et garnis de cols en pierres au rez du sol pour qu’ils aillent bien avec le dallage. Toute la structure sera épaissie à chaque niveau vertical et celui horizontal avec des liens triangulaires et en croix. Les liens seront encore garantis avec des clous.

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eeuroREA1.indburoREA1.indb 114949 222.2.20052.2.2005 223:02:273:02:27