Experimental Study and Theoretical Analysis of Resistance of Steel-Concrete-Steel Sandwich Beams

Abstract

This paper investigates the structural performance of steel-concrete-steel (SCS) sandwich beams interconnected by channel connectors with large interval. Nine simply supported SCS beams with shear span/depth ratio between 1.0 and 5.5 were tested under static load. The contribution of the channel connectors was also studied. All the beams failed because of either tension plate failure in midspan (flexural failure) or tension plate failure in shear span (vertical shear failure). As shear span decreased, failure tended to be governed by shear, whereas for larger shear span, failure was governed by bending. The channel connectors were confirmed to directly affect the vertical shear resistance and ductile performance after critical diagonal cracking. On the basis of the observed failure mode, a mechanical model was developed to predict the ultimate shear resistance of SCS deep beams after critical diagonal cracking. The accuracy of this lower-bound approach was ascertained by comparing with the test results.