Prefabricated enduring composite beams based on innovative shear transmission (PRECO+) : final report

Composite structures are gaining importance due to economic and versatile applications. A new form of shear transmission - composite dowels - permits to design composite girders without an upper steel flange and with enduring shear connection. The composite dowel is produced by cutting a rolled beam with a determined cutting-line into two parts. Due to the high degree of prefabrication shorter construction times and less amount of work are possible. However, few experiences with continuous shear connectors have been gained so far. In the frame of the project the economic efficiency of these composite girders - PRECOBEAMS - was evaluated in detail and could be proven. Wideranging static and cyclic experimental test-series were accomplished, comprehensive FE-Analysis performed and fire-resistance examined as well. The results were presented in a considerably extensive research-report containing design rules for composite dowels in girders under bending loads in accordance to the Eurocode. It includes recommendations for the performance of PRECOBEAMS concerning geometry, reinforcement and fire resistance. Several applications in practice were investigated and some pilot projects were realised which leads to first references in practice. The Pilot-projects well demonstrate the big achievements made in the research-project and the high acceptance and trust in the innovative construction technique along practitioners and authorities.