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Structural assessments of existing older prestressed concrete bridges according to the currently applicable standards and guidelines in Germany generally reveal significant deficiencies in shear reinforcement. Large‐scale tests within the scope of research activities commissioned by the Federal Highway Research Institute (BASt) were carried out at TU Dortmund University to analyze the shear load‐bearing behavior of continuous prestressed concrete beams in more detail. The Arch Action Model (AAM) was derived from the Simplified Arch Action Model (SAAM) to provide a possible analysis method for determining shear contribution from concrete. Thus, the shear capacity of prestressed beams can be determined in a more realistic manner than using the truss model underlying the current state of standardization. The paper at hand provides information and explanations about the SAAM and AAM with regard to their application to real‐world structures for structural bridge assessments. [ABSTRACT FROM AUTHOR]

Private households consume about 30 % of Germany's total primary energy and cause about 15 % of the total CO2 emissions, and so this sector represents a key sector for climate protection targets. Whereas primary energy consumption in buildings is limited by regulations, the production of carbon emissions-intensive materials is only moving slowly into the focus of legislation, regulations and, ultimately, the perception of society. Considering a thermally conditioned building during its life cycle, most environmental effects are during operation. Nevertheless, the grey energy of a concrete structure can add up to 20 % in individual cases. Owing to the carbon-intensive cement production, concrete as a material causes relatively high environmental impacts. Logical options appear to be substituting cement with so called by-products or using recycled additives. In fact, there are only a few projects that have used a resource-saving concrete. In 2010 in Ludwigshafen, one building in a group of buildings was chosen as the first building in Germany to be built almost completely from recycled concrete without increasing the cement content. It was built as a low-energy construction and in a zero-carbon-emissions area. The project was supported scientifically by the Institute of Energy and Environmental Research in Heidelberg and the Brandenburg University of Technology Cottbus. The buildings won the Construction Prize 2011 with the distinction 'best relation between quality and costs'. This paper discusses integral aspects of the use of recycling concrete from the structural design, eco-accounting and materials properties perspectives. It demonstrates the potential and opportunities for the quality-assured use of recycling concrete for sustainable resource management. [ABSTRACT FROM AUTHOR]

Eurocode 2 and the corresponding National Annex were introduced in Germany in 2012. Most of the design provisions for these new standards were adopted from Model Code 1990 and provide a new design approach for ground slabs and footings. For the fib Model Code for Concrete Structures 2010, the punching shear design concept has been revised and introduced in Swiss standard SIA262:2013. This paper presents in detail the design equations for determining the punching capacity according to Eurocode 2, the German National Annex to Eurocode 2, fib Model Code 2010 and SIA 262:2013. Parametric studies have been used to examine the influence of the main parameters (shear span-depth ratio, effective depth, longitudinal reinforcement ratio and concrete compressive strength) on the punching shear resistance of footings. To quantify the level of safety and the efficiency, the design provisions are compared with systematic test series. [ABSTRACT FROM AUTHOR]

Information about the 7th Federation Internationale du Beton International PhD Symposium in Civil Engineering held September 11-13, 2008 in Stuttgart, Germany, is presented. Professor György L. Balázs talked about te objectives of the symposium. Furthermore, there were 170 abstracts submitted and 100 papers accepted for presentation.