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| A sustainable construction – realised with unique formwork elements  An architectural technically sophisticated construction is currently being built in Al Ain – the Desert Learning Centre. For the realisation of this freely-accessible walk-in sculpture, PERI developed a formwork solution using special elements based on proven products. The constant change in curvature and inclination of the components meant that 3D formwork planning was required which was the only way to ensure that the structures could be created using the unique formwork units. In addition to the planning and delivery of the system components, PERI provided reliable logistics and competent on-site support for the contractor Ed. Züblin AG Abu Dhabi.After completion, the Sheikh Zayed Desert Learning Centre (SZDLC) will offer a unique mixture of museums, galleries and natural history exhibitions. Located in the Al Ain region, this prestigious project symbolizes a change of course by the Emirates in the direction of more emphasis on sustainability, and demonstrates that the country attaches great importance to the preservation of both its landscape and culture. Most notable is the observance of strict rules and regulations for the integral and environmentally-friendly construction and operation of the SZDLC. The aim of the builders is to obtain the estidama certificate – the official seal of approval for sustainable construction. Externally, the building is characterized however by its unique design, the particularly high demands placed on the construction work, especially regarding the formwork and temporary support structures. When planning the formwork solution, the maxim was to accommodate the complex geometry by means of different component dimensions. No inclination, curvature, and arching featured in the components is repeated, thus an individual plan of execution was compiled for each wall formwork element. Furthermore, the large component dimensions resulted in high formwork loads during concreting. Among other things, the beams are up to 300 cm high and the walls – which carry the loads of large slab areas into a centred area – are up to 200 cm thick. These boundary conditions made having a very flexible formwork essential – adaptable to all geometries as well as a fresh concrete pressure of more than 100 kN/m². VARIO GT 24 girder wall formwork was eventually selected whereby the individual system components could be arranged according to the projectspecific loads, cross-sections and heights. In order to connect the individual wall formwork elements with each other, in spite of the numerous inclinations and curvatures, the PERI team of engineers also developed some special steel connection components. SB brace frames serve as a quick and safe solution for the single-sided transfer of loads. These divert the concrete pressure which occurs during single-face concreting into the sub-structure. For the Desert Learning Centre, the brace frames are used in combination with VARIO GT 24 girder wall formwork for wall heights up to 3.60 m and concrete pressures of up to 30 kN/m². The slabs with differing thicknesses and ground plans are formed with the MULTIFLEX slab formwork system. Due to the large slab thicknesses, GT 24 lattice girders are used as crossbeams as well as primary beams which facilitates the creation of large spans with a minimum number of moving parts. The proven GT 24 girder is characterized by a high flexural rigidity that in turn ensures low deflections. In those areas of lower heights, PEP slab props carry the MULTIFLEX formwork. For higher slabs – especially in the roofing and at the top of the elevator shafts – PD 8 shoring towers are used. These have been typetested for heights of up to 21.30 m and loads up to 62 kN. The supporting units can be preassembled on the ground, if necessary, and then lifted into the position of use by means of a crane. PERI took on the entire planning of the formwork elements using 3D CAD software. This was absolutely necessary because there are no two curvature or inclinations alike in the entire Desert Learning Centre. Even in the building corners, walls of varying inclinations meet which then merge to form a curvature in the corners themselves. The threedimensional planning and visualization makes the formwork solution clear and understandable to all those involved and thus creates a sound basis for efficient construction work. In addition, the PERI team produced numerous detailed plans using a scale of 1:5 in order to provide the best-possible support for the assembly of the three-dimensional formwork elements on site. Design and construction processes also have an effect on the formwork planning: the building twists upwards like a tunnel resulting in the fact that load transfer is centred in only a few places. A large part of the formwork must therefore remain in position after being installed until these areas have been realised. From the first to the very last of the formwork units, an extremely close eye has to be kept on all formwork and support elements during installation and dismantling – with the immense amount of formwork, and support structures in particular, this presents a major challenge. In addition, construction progress of the basement must continually be taken into consideration as interior work is carried out here whilst shuttering of the walls and slabs is done in the upper floors. The constant, close cooperation between PERI engineers and all members of the Ed. Züblin AG Abu Dhabi construction team has guaranteed optimal implementation of all formworking operations. Among other things during the past 18 months, weekly site meetings have taken place. In spite of the massive proportions of the building, a lightflooded structure with large, diamond-shaped window openings and excellent concrete surfaces has been realised. With their experience and knowhow, PERI design engineers have contributed to the success of this project. The Desert Learning Centre is dedicated to the late Sheikh Zayed and is part of the Al Ain Wildlife Park Resort development project and includes a wide range of hotels, holiday homes, restaurants and shopping centres. The structure resembles a sculpture in the shape of a Moebius strip which blends harmoniously into the desert landscape. An innovative building concept complete with an alternative energy supply and domestic engineering was developed for the Desert Learning Centre. Among other things, the project is one of the first in the world that utilizes large-scale solar cooling. The focus is also on renewable energy regarding power supply – part of the electrical power requirements should be covered using photovoltaic systems. Energy simulations have shown that total energy needs of the Sheikh Zayed Desert Learning Centre is around 40 % less when compared to similar buildings. The aim of all these measures is to secure the Arabian seal of approval for sustainable construction – the estidama certificate. The seal is modelled on the American LEED certification programme and should guarantee an integrated and environmentally-friendly method of construction and building operations. write your comments about the article :: © 2012 Construction News :: home page |