PARTIAL INTERACTION IN COMPOSITE STEEL AND CONCRETE BEAMS WITH FULL SHEAR CONNECTION

The maximum flexural capacity of composite steel and concrete beams wi th mechanical shear connectors and with full shear connection is usual ly determined from rigid plastic analyses. It is generally assumed in these analyses that there is full interaction and that the steel is fu lly yielded. In reality, there is always both partial interaction and an elastic zone of steel that will reduce the strength, but it is assu med that the beneficial effect of strain hardening will compensate. It will be shown that present design assumptions are generally safe for simply supported beams with mild steel sections but can become unconse rvative when dealing with composite beams with very strong steel secti ons, that is when the strength of the steel section (A(s).f(y)) is gre ater than that of the concrete section (A(c)f(c)). (C) 1997 Elsevier S cience Ltd.