Numerical study of reinforced concrete in post-tensioned anchorage zones

Abstract

Prestressed structures have been put into practice in construction since the beginning of this century, but the prestressed structure is concerned with the bearing capacity of anchorage ends. Applying steel reinforcement in anchorage zones can significantly improve the structure behavior and bearing capacity of post-tensioned anchorage zones. Proper reinforcing can relieve congestion and poses difficulty in pouring concrete. Based on materials test data, the nonlinear Finite Element Model (FEM) under local compression was established as part of this study. The nonlinear analysis of the load process was completed based on ABAQUS software. In addition, the model's accuracy was verified by comparing the FEM calculation results with experimental results.Furthermore, the verified FEM was adapted for a parametric study to investigate the influence of various parameters on the bearing capacity, such as the spacing, shape, length of the bearing plate, and reinforcement spacing. The results demonstrate that enhancing steel reinforcement can withstand the forces and stresses and comprehensively improve the local bearing capacity of the specimens; with the decrease of reinforcement spacing, the bearing capacity of the specimen increases, indicating that the reinforcement can dissipate the high stresses among the member from the anchorage zone. The bearing capacity increases with the increase of the bearing plate length, meaning that the bearing plate has a significant influence on bearing the prestressing force in the anchorage zone. Meanwhile, the effect of the bearing plate shape was not obvious. The relationship between the local bearing capacity and the bearing plate length is linear, which indicates that the influence of the bearing plate length on the local pressure properties belongs to the structural layer.