VLoad®: new software to design the capping beam of steel sheet piles submitted to significant vertical and/or horizontal loads
Steel sheet piles have been used predominantly as retaining walls for more than 100 years. In many countries, sheet piles can also resist significant vertical loads from a superstructure, transferring the loads to the soil through point resistance or friction (interaction soil/structure), like any other bearing pile. In certain cases, like bridge abutments, horizontal loads may also be transferred to steel sheet piles.
Bridge abutments, retaining walls of underground car parks and basements are typical applications where high vertical and / or horizontal loads are transmitted to the sheet piles through a capping beam. Currently, the design of the capping beam takes into account the resistance against punching of the concrete (shear failure), and requires some local steel reinforcement. The design is based on national standards and regulations, and may vary by country. Experience has proven that quite often the design of the capping beam was too conservative.
Our R&D department in Luxembourg launched a project to tackle this issue years ago. The aim was to obtain a ‘Technical Approval’ for the design of capping beams submitted to significant static loads. This approval was sought in Germany, and in cooperation with a renowned German consultant, an innovative theoretical concept with quite simple formulas was submitted to the ‘Deutsches Institut für Bautechnik’ (DIBt) in Berlin. Several laboratory testing campaigns were performed in order to corroborate the formulas. Finally, the ‘Zulassung Z-15.6-235’1) was granted to ArcelorMittal in December 2011.
In the meantime, EN 1992, the new European design standard for concrete structures, was officially released in Germany. Consequently, the approval was re-submitted for revision and the current Zulassung was granted in August 2012. Although EN 1992 is a European standard, the National Application Documents may impose different values for some parameters, like the partial safety factors2).
The next logical step was to simplify the use of the new theory which contains a bunch of formulas. The software ‘VLoad’ was developed to actually allow engineers to design cost-effective concrete capping beams in a fast way, including the steel reinforcement, and based on the German ‘Zulassung’.
The software is free of charge and can be downloaded from our website: http://sheetpiling.arcelormittal.com/page/index/name/software . The range of sheet piles covered by the approval is being revised by the DIbT. The interface is quite user-friendly and the user will quickly get acquainted with the software. Nevertheless, if you have any comments or suggestions to improve the software, feel free to contact our technical department firstname.lastname@example.org .
1)Allgemeine bauaufsichtliche Zulassung für Schneidenlagerung zur Einleitung von Vertikal- und Horizontalkräften in Stahlspundbohlen System ArcelorMittal nach DIN 1045-1:2008-08 bzw. DIN EN 1992-1-1 und DIN EN 1992-1-1/NA. DIBt. 2012
2)From a practical point of view, the design based on the German Technical Approval could be applied in any country that uses similar design codes, but it is the responsibility of the design engineer to verify any technical and legal implications.
Released on February 17, 2014