Technical feasibility of a demountable floating body for a demountable stadium.

Appendices Technical feasibility of a demountable floating body for a demountable stadium. J.J. Timmers Master s Thesis June 2013

CONTENTS... 3 CONTENTS... 5 1. FLOATING STRUCTURES... 1 1.1. PONTOONS... 1 1.2. HOUSING... 3 1.3. OFFSHORE... 7 1.4. BRIDGES AND ROADS... 9 1.5. STUDIES... 10 2. STADIUMS... 12 2.1. DEMOUNTABLE STADIUMS... 12 2.2. FLOATING STADIUMS... 14 2.3. STUDIES... 16 3. CONNECTIONS... 19 3.1. FLEXIFLOAT... 19 3.2. HANN OCEAN... 20 3.3. PONTOON CONNECTION... 20 3.4. TEKLOCK SYSTEM... 21 3.5. TENSIONING... 22 3.6. TOOTH CONNECTION... 22 4. LOADS... 23 4.1. LOAD FACTORS... 23 4.2. IMPOSED LOAD... 24 4.3. WIND LOAD... 25 4.4. SNOW LOAD... 25 4.5. WAVE LOAD... 25 5. STATIC STABILITY... 27 5.1. HYDROSTATIC PRESSURE... 27 5.2. BUOYANCY... 28 5.3. TILT... 28 5.4. STATIC STABILITY... 29 6. SPRING SUPPORTED BEAM... 33 6.1. POINT LOAD... 33 6.2. BEAMS WITH A FINITE LENGTH... 37 7. DYNAMIC STABILITY... 39 7.1. MOVEMENTS... 39 7.2. ASSUMPTIONS... 40 7.3. HEAVE MOTION... 40 7.4. ROLL & PITCH MOTION... 41 8. WAVES... 43 8.1. WIND WAVES... 44 8.2. OBSTACLES... 48 8.3. FORCES BY WAVES... 49 9. TRANSPORTATION... 51 9.1. TRANSPORTATION BY SHIPS... 51 9.2. TRANSPORTATION BY ROAD... 54 9.3. TRANSPORTATION BY TRAIN... 54 10. LEGISLATION... 55 10.1. NTA DRIJVEND BOUWEN... 55 10.2. EUROCODE... 55 11. REALISED FLOATING PROJECTS... 57 11.1. FLOATING PAVILION... 57 11.2. FLOATING GREENHOUSE NAALDWIJK... 58 11.3. FLOAT MARINA BAY... 59 12. INTERVIEW RUTGER DE GRAAF (DELTASYNC)... 61 13. LITERATURE... 63 14. LIST OF FIGURES... 67

Floating Structures 1. FLOATING STRUCTURES There are a lot of technologies to create a floating surface. In this chapter the most important and interesting ones will be described. A separation is made between the different systems and companies of the floating elements. 1.1. Pontoons Steel pontoons are often used for temporary stages, floating working surfaces and even as terraces. The structure is very simple mostly it is a box filled with air and some stiffeners. There are a lot of manufactures and rental companies, so only a quick overview is given about steel pontoons. 1.1.1. Hann-Ocean The Hann-Ocean company offers different kind of steel and concretesteel pontoons. These pontoons can be used for a lot functions. Two different pontoons will be described. Containerized pontoons Containerized pontoons are used for floating cranes, performance stages, houses and many other functions. The pontoons have the measurements like an ISO freight container (TEU) and can be handled like that. The connections between the pontoons are described in chapter 3.1. The dimensions and design capacity can be found in Figure 1. Note: feet instead of metres. Figure 1 Containerized pontoons [Hann-Ocean] Concrete steel composite pontoons Concrete steel composite pontoons are steel pontoons with concrete layers on every side. By doing this the lifespan will increase. Floating houses, jetties and breakwaters are functions which can be fulfilled by the concrete steel pontoons. Due to the concrete layer the maximum deck load decreases but they will be less wobble in rough water. The properties are shown in Figure 2. Figure 2 Concrete steel pontoons [Hann-Ocean] 1

Floating Structures 1.1.2. Flexifloat The Flexifloat construction system is a combination of portable, interlocking modular barges and auxiliary attachments, which are used in inland marine and heavy construction applications. All components of the sectional barge system are portable and are designed for road transport by standard highway trucks and trailers. Flexifloat can be quickly connected into larger assemblies of various sizes and shapes by ordinary work crews without the need for special tools or equipment. The resulting platforms are capable of supporting all types of heavy equipment loads in areas that are practically or economically inaccessible to conventional deck barges. (Flexifloat) 2 The pontoons are made from steel and are especially designed for shallow water and inland environments. The modules can be easily transported by truck and the pontoons have a single lifting point. Therefore the handling by crane is simple. The pontoons are mainly for temporary use. The Flexifloat pontoons has its own connection system, this system is described in chapter 3.1. Some specifications of a Flexifloat pontoon are shown in Figure 3 Flexifloat S-70 pontoon, note the units. Figure 3 Flexifloat S-70 pontoon [Flexifloat] 1.1.3. MPS B.V. Modular Pontoon Systems is a Dutch company in Aalst. MPS is a manufacturer of container pontoons. Their modular system is based on a patented coupling system, see chapter 3.4, and their design of steel pontoons. The pontoons are designed and certified for use on inland waterways and coastal areas. (MPS bv). the applications of the pontoons are numerous and are the same as for the other pontoons types. Some specifications of a container pontoon can be seen at Figure 4. In Figure 5 it is clear to see how a steel pontoon can be transported by a truck.

Floating Structures The caisson is mostly made of concrete. This results in a high selfweight and a large draught. As a results there is not a high buoyancy capacity left for the building which is placed upon the caisson. A concrete caisson is a very stable design because it has a low centre of gravity due to the weight, which is very beneficial for the stability. Figure 4 MPS 40' Pontoon [MPS bv] Advantages - Widely used - Stabile - Cheap - Space in the caisson can be used Disadvantages - High self-weight results in large draught - Sinkable - Little buoyant capacity Figure 5 Transport by truck [mm] 1.2. Housing 1.2.1. Closed caisson A floating concrete caisson is mostly a square container see Figure 6. Up on this caisson the building is placed. The caisson is a closed body but the space inside the caisson can be used for several functions like a living floor. Large caissons have sometimes inner walls because the hydrostatic pressure can cause large bending moments in the bottom slab of the caissons. Besides that it also creates partitions in the caisson this is beneficial in case of leakage, only one or several compartments will then be filled with water instead of the whole caisson. Figure 6 Closed caisson [Koekoek] 3

Floating Structures 1.2.2. Open caisson An open caisson is comparable with the closed variant, see Figure 7. In the open variant the top slab is removed. This will reduce the weight and the draught of the caisson. By removing the top slab also the centre of gravity will be lower, this will improve the stability. The walls of the building are placed on the wall of the caisson. This system is used for almost every barge (woonboot) because is relatively cheap. The largest building built with this system is the detention centrum in Zaandam. The floating foundation is 100 meters long and 22 meters wide. (Cement and Graaf). The biggest disadvantage of this system is the depth, for a normal house the draught is usually 1.5 meters. (Graaf). Most waters in Netherlands are very shallow the depth varies from 1 to 1.5 meters. The same advantages and disadvantages hold for the open caisson as for the closed caisson but the disadvantages about self-weight and buoyant capacity are less present. Advantages - Widely used - Stabile - Cheap - Space in the caisson can be used Disadvantages - High self-weight results in large draught - Sinkable - Little buoyant capacity 1.2.3. Pneumatic caisson The pneumatic caisson has no bottom slab, see Figure 8. The buoyant force comes from the compressed air between the water and the caisson. The buoyant force is lower than an open caisson with the same dimensions because the displacement of water is less. Because this variant has no bottom slab the centre of gravity is on a higher place that makes this variant less stable. It is a risky system, if the compressed air escapes the caissons sinks. Actually this system is not often used for floating buildings but for other functions, like tunnels. Figure 8 Pneumatic caisson [Koekoek] 1.2.4. Caisson filled with EPS In this variant the caisson is filled with polystyrene foam blocks. These EPS blocks have a low weight so the caisson has lower draught and a higher buoyant force. Besides this advantage the caisson cannot sink anymore because the caisson is filled. For the same reason the thickness of the walls and slabs will become smaller. 4 Figure 7 Open caisson [Koekoek] This variant is often used in Canada and is in the Netherlands adopted by Ooms bouwmaatschappij. In het 1980 s the Canadian company International Marina Floatation Systems Inc. (IMF) started constructing houses and other buildings with EPS and concrete. The concrete around the EPS blocks contribute to the stiffness en structural unity of the floating body. (wonenopwater).

Floating Structures On Figure 9 the construction method is clearly explained. First a concrete floor will be made when the floor is ready the EPS-blocks are put together to made a core of EPS blocks. The third step is to wrap the EPS core with reinforcement. This reinforcement is needed for the concrete walls and top floor. In the next steps the formwork will be placed and the concrete poured. When the formwork is removed the floating body is ready to build a house on top of it. Figure 9 Construction order [Ooms] 1.2.5. Flexbase Flexbase is a cooperation between Dura Vermeer, Dutch Construction Company and Unidek, European biggest producer of EPS. The main difference between the Flexbase variant and IMF variant is, that there is not a shell around the EPS blocks but there are interior concrete beams and is composed of multiple layers of EPS blocks. The floating bodies are constructed on the water see Figure 10 Construction order. The first layer(s) of EPS blocks are connected with each other with scarf joints (haaklas). When the first layer is connected and finished EPS blocks will layered upon each other and glued together. Between the last few layers of EPS block there will be space left for the concrete beams. The next step if pouring the concrete in the open spaces. When the concrete is hardened the reinforcement can be placed and the concrete can be poured to create the floor. After hardening of the concrete the floating body is finished. This variant is used for the floating greenhouse in Naaldwijk and for the floating pavilion in Rotterdam, more information can be found in chapter 11.1 Floating Pavilion. Figure 10 Construction order [Flexbase] The biggest disadvantage is that the concrete beams are in situ poured in the gaps between the EPS blocks but before the pouring is done the structural rigidity is very low. This means that during pouring of the concrete the floating platform will deform a bit. The hardened concrete beams will have this deformation. (M. Koekoek). This disadvantage could be taken away if the structure is built on land instead of the water. A second disadvantage is that the EPS structure is not fully protected by concrete so there is a chance that the EPS can break or worse disconnects from the structure. 1.2.6. Flexbase light Flexbase light is a product from the same company as Flexbase. This product is especially made for floating sport fields. Flexbase light is designed to combine a water retention area with a sportfield. 5

Floating Structures The Flexbase Light foundation consist of EPS plates with on both sides a glass fibre reinforced cloth. Flexbase Light system is based to create a equilibrium situation on the ground level so that when there is enough water the sport field will float. The principle is depicted in Figure 11 Flexbase light system. The properties of a floating sport field according to Flexbase are: - Maximum irregularity is 7 mm; - Maximum deformation is 4-10 mm; - Shockdamping, 55-70 %; - Lifespan > 5 years. 1.2.7. Steel tubes Steel tubes are not often used for floating bodies for housing but in the offshore world it is more often used. Steel needs maintenance, for floating bodies this is a big disadvantage. The dead weight of steel is very large but the strength is also large so floating bodies can be constructed with less material. Due to the low weight the centre of gravity will be higher, that is unfavourable for the stability of the structure. For offshore structures this problem is solved by bringing the floating body under water. For floating structures like housing this is impossible due to the maximum depth of inland waters. In Middelburg a floating house (Figure 1) is constructed with steel tubes the problem of static stability is solved by filling the tubes with concrete which results in a deeper draught. Figure 12 Floating house Middelburg [woonen] 6 Figure 11 Flexbase light system [Flexbase]

Floating Structures 1.3. Offshore 1.3.1. Pneumatically stabilised platform (PSP) A pneumatically stabilised platform is a platform which is composed of multiple cylinders of concrete or steel see Figure 13. These cylinders remain together by a rectangular platform at the top of the cylinders. The cylinders can have all kinds of diameters for small structures a dimension of decimetres and for large structures the diameter is several meters. The buoyancy comes from the air pressure between the water surface and the top deck. Figure 14 Detail air exchange Figure 13 PSP platform The pneumatically stabilised platforms are very stable because the air in the cylinders is connected with each other so the air can flow from one cylinder to the other. In case of waves the water level changes as a result the air flows from one cylinder to another see Figure 14 because of this movement the platform stays stabile. PSP s may be deployed in regions with extreme wave heights. (Floatinc.) 1.3.2. Semi-submersible structures Semi-submersible structures are often used in the offshore branch. Those platforms are very stable because the design is in such a way that waves forces are minimized. Figure 15 shows an example of a semi-submersible structure. Semi-submersible structures have a minimum amount of surface around the water surface. On the water surface the wave forces are the highest so with minimum surfaces on that place the dynamic stability is better. With this reason these semisubmersible structures perform well at heavy ocean conditions. The working platforms are raised above the sea level by column tubes or ballast structural elements. A disadvantage is that these platforms have a deep draught between 15 en 50 meters. Typical examples of semi-submersible structures are oil drilling and oil production platforms. 7

Floating Structures Figure 15 Semi-Submersible 8 1.3.3. Tension leg A tension leg platform is vertically moored to the sea bottom with tension legs see Figure 16. Tension legs are a group of tethers or chains. These tension legs have a very low axial elasticity, so a high axial stiffness. Because the low elasticity the platform is not sensitive to vertical motions because the tension legs do not extend. These platforms are often used for oil production and drilling but there are plans to build wind turbines with tension legs. This has an advantage that wind turbine farms can be built further from the coast. Researchers of Massachusetts Institute of Technology and the National Renewable Energy Laboratory investigated this option and concluded that it would be cheaper than fixed towers. Figure 16 Tension leg 1.3.4. Spar/Buoy A Spar is a long slender body that floats vertically see Figure 17, with its centre of gravity below its centre of buoyancy. All other floating platforms have their centres of gravity above their centres of buoyancy, and could flip over. Spars are inherently safe because they cannot flip over. In addition to inherent safety, a Spar is the most stable floating platform for supporting risers and guiding top tensioned risers. The deep draft of the Spar minimizes vertical motion and Spars inherently pitch (rotate) around their keel (bottom), close to where the risers exit. The keel then is the place of minimum vertical and lateral motion, ideal for supporting the risers (Technip).

Floating Structures 1.4.2. Floating Road Hedel Several Dutch companies developed a prototype of a floating road and tested it, see Figure 19. The floating road was situated in Hedel in the province Noord-Brabant in the Netherlands. The design speed of this floating road was 80 km/h. The floating road is especially suitable for temporary use. The road consists of aluminium pontoons. One pontoon has a width of 5.4 meters a length of 3.5 meters and a height of 1.6 meters. The pontoons dead weight is 3100kg. 1.4. Bridges and roads Figure 17 Spar/Buoy 1.4.1. Pontjesbrug Also some floating bridges and roads doe exist. Maybe the most famous one is the Pontjesbrug in Willemstad, Curacao see Figure 18. This bridge is constructed on multiple pontoons which are connected through the bridge deck. The bridge is 168 meters long and was built in 1888. The road is designed with a maximum load of only one vehicle at a time of 8000kg. The road is also suitable for pedestrians. The design load for pedestrians was 4kN/m 2. During the design the highest wind load is used to calculate the wind force. For wind waves, a typical wind wave of length of 6.3 meters, an height of 0.30 meters and a period of 2 seconds is used. (Maljaars) Figure 19 Floating road Hedel Figure 18 Pontjesbrug 9

Floating Structures 1.5. Studies 1.5.1. Maarten Kuijper Variant Maarten Kuijper has made a design for a floating foundation during his graduation project. His final design is a frame system which is composed of EPS blocks; see Figure 20 One element has a dimension of 3 meters wide and 12 meters long. These elements can be coupled to each other. Every element has 16 EPS blocks with a wide and length of 1.5 meters. The EPS blocks have a special shape when combining the blocks some space will be left. In this space concrete will be poured and so concrete beams will be formed. In longitudinal direction there is one concrete beam and in transverse direction, depending on the design every 1.5 or 3 meter there is a concrete beam. On top a beam grid floor is built. The floating elements are coupled together with pretension cables. These cables are put in the concrete beams. The pretension can be done in one direction or two directions. For smaller platforms it is possible to connect the element with a bolted connection. More detailed information can be found in the thesis form Maarten Kuijper [M. Kuijper]. see Figure 21. The shape of one element is a hexagon. The EPS core consists of prefab EPS discs. When using different number of discs the height and buoyancy can be varied. The EPS core is also the formwork for the concrete frame. Concrete that is used is selfcompacting high strength concrete. Figure 21 Ties Rijcken system The elements can be connected on two different manners. The first manner is simply using internally threaded couplers, steel rings and bolts. The second manner is to pour multiple modules in one time. Figure 20 Maarten Kuijper system 10 1.5.2. Ties Rijcken Ties Rijcken graduated at the faculty of Industrial design of the Technical University Delft. His graduation was projected a new concept for a floating foundation. Together with ABC Arkenbouw he realised his graduation thesis. The floating foundation of Ties Rijcken is built from elements that consist of a core of EPS around this core there is a concrete shell

Floating Structures 1.5.3. Aqua-struenda This variant also uses EPS blocks in combination with concrete. The floating body has an EPS core with concrete walls as depicted in Figure 22. On top of the core a concrete floor with a beam grid is placed this grid has a height of 600 millimetres. On this beam grid a concrete deck floor is constructed. In the space between the beam grid and the deck floor there is space. One element is 15.8 meters wide 108 meters long and has a thickness of 3.5 meters. The measurements are derived from a planning grid of 3.6 meters which is quite a standardized dimension for housing. (ecoboot) Figure 22 Aqua-struenda system 11

Stadiums 2. STADIUMS 2.1. Demountable Stadiums Demountable stadiums are built all around the world and there a many different types of stadiums like multifunctional stadiums, stadiums just for one sport and temporary stadiums. In this study only temporary or demountable stadiums are of interest. In this chapter an overview is given about different demountable stadiums techniques. Temporary stadium and grandstands which are constructed with a scaffolding structure is a proven technique. There are a lot of references for scaffolding stadiums. Scaffolding structures are demountable and portable. Scaffolding is often used as temporary structure and can be rented at many places. The system consists of steel or aluminium pipes which can be easily connected to each other. The erection time is very short. An example of a grandstand with a scaffolding structure is depicted in Figure 23. With these systems even a roof structure is possible to construct. The foundations for such stadiums are wooden plates, 400*400mm. [Den Hollander] also possible to construct a second tier with a modular system. Figure 24 depict a modular steel structure. The highest built structures are around 30 meters. [den Hollander] Figure 24 Modular steel grandstand [Nussli] The properties of the different techniques are shown in Figure 25. 12 Figure 23 Scaffolding grandstand [Nussli] Modular steel structures are also often applied for stadiums. These structures are a bit less flexible and transportable but it is possible. The modules are a bit bigger but remain flexible and adaptable. It is

Stadiums World of Football This stadium, Figure 26 was used during the world championship in 2006 in Germany. It is a replica of Berlin s Olympic stadium on a scale 1:3. This stadium was set up in front of the Reichstag. It provides a place for football fans to watch the games on big screens. The capacity of the stadium is 10.000 people The stadium had eight skyboxes, a TV studio, a camera tower, disabled platforms and a CD tower with a 20*18 meters footprint for concerts and shows. The total surface area was 40.000 m 2. Altogether 1.150 tons of material, supplied in 65 truck loads, was erected for this event. [Nussli.com] Figure 26 World of Football stadium Figure 25 Comparison Scaffolding with Modular structures 2.1.1. Nussli Nussli is a leading company on temporary structures and it operates all over the world. Their core businesses are grandstands, modular stadiums, booth constructions and pavilion constructions along with the overall delivery of event structures and exhibition structures. [nussli.com] Nussli offers complete modular and temporary stadiums or grandstands. They have a lot of experience with construction temporary stadiums. They use mainly scaffolding to construct the stadiums and grandstand. They can even build temporary roofing. Nussli designed a lot of temporary stadiums two examples from Nussli will be described. 13

Stadiums Fortuna Dusseldorf In 2011 the Eurovision Song contest was hosted in the stadium of Fortuna Dusseldorf. During the Eurovision Song contest the home games of Fortune Dusseldorf were played in a temporary stadium which was built directly near their normal stadium see Figure 27. The stadium's total approximate spectator capacity of 20,000 is divided into seating for about 12,500 fans and standing room for an additional 7,500. The functional rooms for the teams will be set up in fully equipped containers located behind the main grandstand. The stadium was built in just 8 weeks and was leased during the period. The stadium was built in accordance with the German soccer association and the German soccer league guidelines. Baseball Figure 28 San Diego floating stadium Football 14 Figure 27 Fortuna Dussseldorf 2.2. Floating stadiums 2.2.1. San Diego In 1964 a local firm Boyle Engineering in San Diego proposed a floating stadium that should float in the Mission Bay. The stadium should hosting football, major league baseball and aquatic event and the stadium would seat over 50.000 fans on a site near Fiesta Island. The stadium would consist of three huge sections according to the Boyle Company. A grandstand, seating about 13.000 would be landlocked and is the centre section. Two wings of 20.000 seats each would float on pontoons and could be easily maneuverer into various configurations to support the spectator requirements of different sports see Figure 28 For baseball, the two wings would be attached to the centre grandstand. For football, the wings would be disengaged and floated over to cover both sides of a separate playing field. With other configurations fans could watch water sports on the bay. Requiring only eleven feet (3.35 meters) of draft, the sections would move easily. The price tag was estimated on a $20 million that is about the same costs as a conventional stadium in 1964. Unfortunately the stadium has never been built; instead a conventional multipurpose facility was approved and finished in 1967. [Crawford]

Stadiums 2.2.2. Michael Burt Michael Burt is an Israeli emeritus professor at the ITT, he suggest that mega-events should be organized on floating structures. When the event is closed the floating structures can move on to the next city with a harbour and be a platform for the next football match or concert. For the Olympic Games he suggested a stadium with 150.000 seats with measurements of 300*400 meters. This stadium is the centre point when a city doesn t has enough facilities extra floating structures housing for the athletes can be attached. He got the idea for the floating stadium 20 years ago but did not develop it further before colleagues Yechiel Rosenfeld and Anna Sorkin offered to help him fine-tune and promote the plan which has only become more timely and feasible as research into space technology has led to the discovery of new and lighter materials. The trio has looked at a world map and estimates that five floating stadiums can cover the Baltic Sea, the Mediterranean, the Caribbean, the Indian Ocean and Asia. [play the game] sustainable practices. The stadium houses 180 VIP boxes and areas, office space for FIFA and local organizing committee members, as well as an opulent range of hospitality features, a hotel, a casino, a shopping centre, restaurants and a fitness centre. [sportsmagazine] Figure 30 Qatar 2022 stadium by stadiumconcept.de 2.2.4. Bigfoot Heneghan Peng architects made a design for an ideas competition in 1997 for a football stadium at Santa Monica State beach in order to entice football teams back to LA which had been deserted by two football teams in previous years. The name of the stadium is Bigfoot. The form of the ship/stadium is derived from a super tanker into which a football stadium for 80,000 has been inserted see Figure 31. The form of the ship s hull is modified slightly to accommodate the idealized stadium. Under-stadium activities of concession stands, access ways and services occupy the interstitial space between the stadium and the hull. [hparc.com] Figure 29 Michael Burt design 2.2.3. Qatar 2022 In 2022 the FIFA world cup will be in Qatar. Stadiumconcept.de and ArenaCom made a proposal for a floating offshore stadium for 65.000 visitors. The size of this stadium is almost a big as the RMS Queen Mary 2, Figure 30. The stadium would be founded on a large floating disk and constructed using renewable materials and Figure 31 Bigfoot floating stadium 15

Stadiums 2.3. Studies There are some master theses made about floating stadiums these theses are made within the faculty of architecture at Delft University of Architecture. 16 2.3.1. Innovative Stadium Design Building up the stadium out of several modules, able to function on its own and as several configurations is the solution for a flexible stadium. Besides the flexibility, the functionality of the design is normative to create a realistic stadium design. The several modules, a configuration with two tiers and a configuration with three tiers are developed for the Innovative Stadium Design. To transport the stadium over water, the stadium will be built on pontoons. For optimal transport, the main requirement was to be able to cross the Panama Canal. This determines the maximum dimensions for the pontoons and guarantees the optimal usage and transportability. All the separate pontoons will have to be stable and will be coupled to one rigid stadium pontoon. For optimal pontoon usage, the stadium has been separated in four elements; the pitch, first and second configuration and the entrance. By using the same entrance pontoons in both configurations, an optimization was made. To get a realistic and feasible stadium design, the scale of disassembly and the building time are the most important aspects of assembly and disassembly. The stadium design consists of several modules, in which platform design is the starting point. Platform design results in standardization of the modules which limited the number of loose elements and thus the building time. The standardization is visible in the modules which results in the stadium, but also in the added functions like toilets and SUP's. These functions will be added as universal units. [Fransen, Vermeulen] Figure 32 Innovative Stadium Design study 2.3.2. Olympic fleet The Rotterdam Olympic stadium is built up out of floating elements and temporary components. A traditional stadium bowl is cut into separate parts to increase the post-olympic legacy potential. The floating stadium elements can be reused as housing elements elsewhere in the Netherlands and abroad, but can also be used for other purposes such as flood shelters. The temporary parts can be reused as stands for different sport clubs and temporary events. The Rotterdam harbour area is moving towards the sea. The Rotterdam Stadshavens are developed into the pilot project for floating buildings. A number of stadium elements are reused into a floating residential community in the Waalhaven area see Figure 33. The elements are reminders of the Olympic Games of 2028 and form the infrastructure and architectural expression for the transformation of this area. [Goeman] Figure 33 Olympic fleet