RIJEKA’S TORPEDO LAUNCH PAD STATION PRESERVATION Ivan Marović University of Rijeka, Faculty of Civil Engineering, Rijeka, Croatia [email protected] Ivica Završki University of Zagreb, Faculty of Civil Engineering, Zagreb, Croatia [email protected] Diana Car-Pušić University of Rijeka, Faculty of Civil Engineering, Rijeka, Croatia [email protected] From the middle of 19th century till the middle of 20th century Rijeka’s industrial developments were known world wide. One such unique and genuine development for sure is a torpedo. Every torpedo had to pass very difficult testing processes therefore it was necessary to build such facility which enabled simulation of all launch positions. Today, Torpedo launch pad station facility has attribute of cultural good although is rather devastated. Consequently, this paper will give an overview of what should have been done and was not, and an overview of what is being done to salvage and preserve such an important and unique monument of technological activities of Rijeka and its citizens that endures time. KEYWORDS: industrial heritage, maintenance management, preservation, reuse. INTRODUCTION City of Rijeka is situated on the shore of Kvarner bay, the northernmost part of Adriatic Sea, where the Mediterranean is closest to the countries of middle Europe. As being in background of Kvarner, Dinaric Alps are at lowest altitude therefore is the easiest crossover from sea side deeper into land towards European countries. Good geographical position of Rijeka provided good communication post, which was first noticed by Romans and Greeks, and can be found in charts of famous chart maker Claudius Ptolemaeus. Industrial developments in Rijeka are strictly connected with developments which followed the Industrial Revolution such as development of steam engine. In the late years of 19th century town grew rapidly and good geo-communication position helped Rijeka to become industrial centre and important sea port of that time. One of many technical and technological developments of that time for sure is torpedo. Torpedo idea was born and developed in Rijeka. When the retired officer of Austrian Marine Artillery captain Giovanni Luppis returned to his home town Fiume (Rijeka) he tried to achieve his many years evolved idea of “Salvacoste” (Coast saver), a new long distance self remote navy weapon. As captain Luppis had no technical knowledge as well as resources for development and improvement of his idea, introduction to Robert Whitehead made him one step closer to its fulfilment. Robert Whitehead was British machine engineer and manager of the local factory and iron foundry in Rijeka. He developed Luppis’ idea and made completely 446 new product called torpedo which was the most advanced navy weapon of that time. From the middle of 19th century till the middle of 20th century the highest class torpedoes were designed, build and tested in Rijeka. According to the factory’s available documents during that period of time there were build 20.383 torpedoes, 1.053 launch tubes and 1.368 high pressure compressors. Before explosive filling and final use, every torpedo had to pass very difficult testing processes which included launch of every torpedo at least four times. For such complex testing processes facility for launching torpedoes logically arises as necessary. Torpedo launch pad station in Rijeka was and is first facility of such kind. Torpedo launch pad station Torpedo launch pad station was used for torpedo final testing purposes and became crown achievement of this revolutionary invention. Facility was used for torpedo launching in order to test horizontal and vertical movements and adequate redesign if necessary. Facility provided simulation of torpedo launching below, from and/or above sea level. Launch pad station in Rijeka was conducted in two phases. First phase started at 1929 when the eastern part of this facility was build. In the period from 1936 till 1945 the western part was build and the whole facility took the shape which we know today. Facility stayed in use until 1966, when factory sold torpedo construction rights to other factories around the world. Building of launch pad station was made of reinforced concrete, steel, stone, wood and glass. Whole bearing structure was made of reinforced concrete and steel, while wall fillings and facade walls were made of stone blocks and hollow bricks with vertical cavities in combination with glass. Roof structure was made of wood. On the south side of the roof structure was constructed wooden observation post which was enhanced in relation to remaining roof structure. Torpedo launch pad station main parts are shown on Figures 1 and 2: 1 – passage between factory and launch pad station, 2 – access to the launch tubes, 3 – movable launch tubes, 4 – derricks, 5 – observation post. 5 Figure 1: South facade of torpedo launch pad station 447 4 4 1 3 1 3 2 Figure 2: Torpedo launch pad station ground plan Figure 1 gives an overview of the facility from position of working platform upwards. Foundations are not shown. Facility was founded in very specific conditions; partly on shore and partly on piles and piers in the sea. Most part of the facility lies just above the sea level. The average sea depth in the area of launch pad station is ten meters. Present state of facility Today, Torpedo launch pad station is rather devastated. All structural elements experienced specific amount of damage. Considering proportion and type of reinforced concrete structural damage, rehabilitation can be performed by structural elements reparation or their complete removal and production of new elements exactly the same dimensions. It is of great importance to act quickly because of the years of none maintenance will lead this unique facility to structural collapse (Marović, Završki, Car-Pušić, 2009). Figures 3 to 5 present the general state of Torpedo launch pad station today. Figure 3: East view of the facility Figure 4: West view of the facility 448 Figure 5: South view of the facility In the present maritime conditions the steel reinforcement in the concrete structure has been subject to corrosion induced by chloride ions which caused progressive decay of the reinforced concrete structure during such long period of time. The harmful effects of corrosion can be seen in the reduction of the effective cross-sectional area of the reinforcement bars and their ductility, longitudinal fracturing and flaking of the concrete protection, the loss of adhesion between the concrete and the reinforcement. Conducted examination of facility Engineering methodology of estimating the current condition of structure was used, which included studying the existing documentation, visual inspection of the structure, field and laboratory testing on specimens taken from the structure, preliminary classification of damage and calculation of residual bearing capacity (Bjelanović et al, 2007; Grandić et al, 2008). The aim of laboratory tests was to define the condition of structure materials, which included material properties of the concrete and the corroded reinforcement, permeability of the concrete as well as the amount of chloride ions in the concrete in order to estimate influence of its age and the effect of aggressive maritime environment to general durability of the facility. In his work Kovačević (2007) gave the results of laboratory tests detail damage classification of main structural elements of Torpedo launch pad station. Reinforced concrete elements, due to corrosion overgrow, cast out protective concrete layer making the reinforcing bars directly exposed to impacts of surroundings especially under the working platform. Concrete construction framework which use to be a support for entire roof truss and derrick girders, cast out protective concrete layer because reinforcement is well saturated with sea salt chlorides. Most damaged frames of this facility are positioned in the middle of the construction near the shore boundary where the load is most significant. Regarding the type and quantity of structural element damage, it is possible to approach the rehabilitation of facility by reparation and/or substitution of damaged structural elements. Table 1 gives an overview of reparation and/or substitution proportion of certain element groups divided into west and east part of the facility (see Fig. 5: west part – left, east part – right). 449 Impact of sea salt chlorides penetration into concrete elements can be seen on Figure 6 and 7, while the power of sea waves can be seen on Figure 8 and 9. Figure 6: Working platform (front facade detail) Figure 7 : Working pl atform ( shore bou ndary detail) Figure 8: Working platform (inside facility) Figure 9: Damaged pier (cavitation impact) There is no constructive element which wasn’t damaged due reinforcement corrosion. On most structural elements major part of reinforcement cross-section has been partly corroded, while on some other parts the reinforcement is completely corroded and missing. Most damaged frames are positioned in the middle of the construction near the shore boundary where the load is most significant. Whole construction is exposed to extreme loading conditions (wind pressure and breaking waves) during south and south-east winds called Oštro and Jugo (Marović, Završki, Car-Pušić, 2009). Especially jeopardized and very high risk zones are concrete beam supports where the lack of mechanical connection can cause the collapse of facility. 450 Table 1: Overview of the reconstruction work Structural elements West part East