Numerical study on the shear failure behavior of RC beams subjected to drying

Abstract

To improve the aging management of nuclear power plants (NPPs) and to extend the plant life by allowing long-term operation, a numerical model, which can evaluate the changes in the structural performance due to drying (i.e., drying shrinkage, resultant shrinkage-induced cracks, and property changes due to desiccation), is proposed. For the numerical model, a 3D rigid-body-spring-network model (RBSM) combined with a truss network model was adopted, and moisture transport, subsequent drying shrinkage, and changes in physical properties were implemented. In this study, four beams were analyzed, with two beam sizes without stirrups being subjected and not subjected to desiccation, respectively. All beams considered for the numerical investigation are shear critical. The numerical model produced reasonable results for the following points: 1) a strain distribution of rebar after drying, 2) changes in diagonal cracking patterns, and 3) trends in the load–deformation relationship, especially with the diagonal-cracking strength showing agreement with the experimental result. However, the ultimate shear strengths did not correspond with the experimental results. Based on previous research, this discrepancy can be improved by considering the “dowel effect” at the shear failure.