Steel is one of the most fascinating materials in the building industry. Very fine steel structures are able to absorb enormous forces. In the past decades, ABT has designed special structures using this material. Over the years, steel had become a material that held no secrets. Or so it seemed. Improved calculation methods and new construction principles resulted in greater material efficiency. So much is true. Yet, high-strength steel is a new type of steel with particularly improved properties compared to ‘ordinary’ construction steel. Even greater forces can be absorbed by this type of steel, allowing the construction of even more slender structures.
The centre for life sciences (Het Centrum voor Levenswetenschappen), the Eye Film Institute, the Ziggo Dome, the National Military Museum Soesterberg , and a large number of bridges all make use of eye catching steel structures. The number of examples of remarkable steel structures developed by ABT over the past decades is continually expanding. ABT is continuously balancing on the border between the possible and the impossible, while always keeping in mind the functionality of the structure.
Sometimes, these structures are not that obvious. For example, when we designed the bottom floors of the Montevideo tower in Rotterdam, which has a height of over 150 metres. These floors had to be kept as open as possible, while also supporting the full weight of the entire tower. We were able to meet this requirement only by including columns of high-strength steel.
High-strength steel has a different chemical structure to regular steel, is manufactured using another rolling procedure, and comprises a different type of alloy - all resulting in a substantially raised yield point. Regular steel, as applied in structures, has a guaranteed yield point of 235 N/mm2 or 355 N/mm2; high-strength steel has guaranteed yield points of 460, which may even be extended to 1100 N/mm2. Moreover, this material is more easily welded than regular carbon steel. High-strength steel offers many possibilities to make use of steel, and more efficiently than ever. In our efforts to reduce the use of materials in buildings, high-strength steel is one of our important spearheads.
And by using 3-D calculation programmes, the material efficiency is raised even further. They enable the calculation of many more constructional variants. One of these tools is the parametric material optimisation - a software programme we developed ourselves. In addition, by using the advanced EEM programme, we are able to investigate the actual forces present in the connections. This insight will enable us to make these connections even more economical.
And, last but certainly not least, ABT is conducting research into ‘intelligent’ steel structures. In principle, structures are calculated to be able to bear the heaviest loads, under the most adverse conditions. To withstand such forces, a lot of material is needed. Which is a shame, really. After all, these adverse conditions may never actually occur! We are now investigating whether the internal mechanical forces within a frame structure may be influenced using a system of jacks and cables. As a result, the structure could be temporarily subjected to heavier loads. Or they may be made suitable for possible overloads as a result of water accumulation, for example. Thanks to this principle, the structure might be realised in a way that requires substantially less material.