Tension stiffening in concrete beams. Part 2: Member analysis

Abstract

Based on finite-element analysis of cracked reinforced concrete beams, a tensile stress block was proposed in part 1 of this paper. Here, the proposed tensile stress block is contrasted with existing ones developed by others to provide an overall review. The proposed tensile stress block is then applied to a section analysis of beams to evaluate the moment-curvature curves of typical beam sections. The section analysis results are compared with available experimental results and empirical curves given in design codes to demonstrate the validity of the tensile stress block. Subsequently, the proposed tensile stress block is applied to member analysis by first dividing the beam member into short segments and then applying section analysis to each segment to evaluate the load- deflection curves of typical beam members. The member analysis results are checked against finite-element analysis results and available experimental results to fine-tune the tensile stress block and verify the accuracy of the finetuned tensile stress block. Such member analysis could be extended to multi-level analysis of frame structures for their full-range load-deflection behaviour at the elastic, post-crack and post-peak states.