Shear connection in beams that support composite slabs - BS5950 and EN1994-1-1

The validity of the provisions of both the British and the European codes of practice for design in composite slabs of shear connection for beams has been questioned in recent publications, based on test results that show sub-standard shear resistance and low slip capacity. These issues are explained and discussed. The provisions of EN 1994-1-1 are generally more relevant and conservative than those of BS 5950, but its coverage of the problem areas is not complete. Although further research is needed, it is recommended that published guidance to designers of beams that support composite slabs should at once be revised to take account of the Eurocode rules, and of the conclusions given here.

Some combinations of parameters where particular care is needed are described.

R. P. Johnson, FREng, FIStructE, FICE
Emeritus professor, University of Warwick