British Constructional Steelwork Association

This paper proposes a new concept and algorithm to transfer brittle and arbitrary load-slip curves into an effective shear resistance suitable for Eurocode 4. This algorithm is specifically for demountable shear connections of composite beams which do not exhibit ductile behaviour as required in EC4. The algorithm is validated with numerical finite element models which have been calibrated against experimental results. The algorithm extends the scope of the code to cover demountable shear connections: it allows the EC4 (EN 1994-1-1) rules remain applicable for the evaluation of the plastic bending resistance of composite beams with partial shear connection.

BCSA and Corus engaged Atkins to develop a simplified carbon calculator design tool, which could be used to evaluate the carbon footprint of typical steel–concrete composite bridges. A key requirement was to allow rapid evaluation of a range of preliminary design options based on minimal calculated quantities for each option, using typical default assumptions. In addition, the tool needed to be flexible enough to allow the designer to enter more detailed data to override default assumptions and quantities should they become known more accurately. This paper describes the development of the design tool, assumptions used in setting the default parameters and commentary on the sources of information used for the carbon data. An illustration of its use in comparing a typical steel–concrete composite bridge with an equivalent concrete bridge is also provided. It is intended that the design tool will be used by bridge designers to help quantify the embodied and operational carbon dioxide of steel–concrete composite bridges at all stages in their life-cycle, facilitate reductions in the carbon dioxide footprint during construction and maintenance by allowing alternatives to be rapidly assessed, and benchmark projects to facilitate continuous improvement with respect to carbon dioxide.