Evaluation of Cracking and Serviceability Performance of Lightweight Aggregate Concrete Deep Beams

Abstract

This paper investigated the diagonal crack propagation and serviceability performance of fifteen deep beams fabricated using lightweight aggregate concrete (LWAC). Experimental variables included the shear span-depth ratio, beam section depth, and bearing plate width. The test results were reported in terms of crack propagation, diagonal crack width, diagonal cracking load, and size effect on the serviceability of deep beams; they were also employed to establish a relationship between residual shear bearing capacity and maximum diagonal crack width for such components. In addition, the crack width limits in current code provisions were utilized to further evaluate the serviceability of LWAC deep beams. The test results revealed that the diagonal crack propagation is almost independent of the variation of beam depth, while the diagonal crack width exhibited an obvious increasing trend as shear span-depth ratio or bearing plate width increased. At service load level, the crack width limit of 0.4 mm stipulated in ACI 224-R-01 can be satisfied by LWAC deep beams with horizontal and vertical shear reinforcement ratios more than 0.3%.