Modeling structural behavior of precast concrete pipe with single elliptical steel cage reinforcement

Abstract

Using single elliptical (SE) cage reinforcement in reinforced concrete pipes (RCP) can reduce both the needed reinforcing steel and labor for manufacturing double and triple steel reinforcing cages. However, there is currently no robust tools to predict the structural behavior of RCP with SE reinforcement. In this study, non-linear 3D finite element model was developed to evaluate the load capacity of SE reinforced RCP. Model predictions were validated using experimental results on corresponding full-scale pipes. The model simulated load–deflection curves of RCP under the three-edge bearing test (TEBT) and predicted its load capacity with an average error of 9%. A parametric study was conducted to investigate the effects of SE cage rotation on the load capacity of RCP. It was found that rotation had minimal effect on the elastic behavior and stiffness of the pipe up to 1 mm vertical deflection. However, SE cage rotation had greater significance on the plastic response of the pipe when the steel reinforcement became fully engaged. The proposed model could provide a basis for developing design charts for RCP with SE reinforcement and quantify possible effects of SE reinforcing cage rotation on pipe load capacity.