Large-Scale Experimental Investigation of Deformable RC Box Sections

This paper presents the results of an experimental investigation of deformable reinforced concrete box sections under eccentric loads. A total of eight large-scale tests were carried out to provide experimental evidence for the ultimate load-carrying capacity and failure mechanisms in deformable thin-walled box sections. The main parameters investigated in this program were the ratio of transverse bending to in-plane capacity of the walls in the box section, as well as the degree of load eccentricity. The experimental investigation has shown that plastic corner hinge lines will form, and that the length over which these extend at failure will vary with the ratio of transverse bending to in-plane capacities, and the degree of eccentricity. It was found experimentally that the spread of plasticity in a deformable box section increases logarithmically as the ratio of bending to in-plane capacity decreases. Finally, the experiments have shown that the space truss theory for combined bending and torsion, which does not take distortion into account, will lead to unsafe capacities, and therefore a modification to the space truss theory is suggested.