Finite Element Analysis of Reinforced Concrete Joints Subjected to Multi-Axial Loading

摘要

The authors conducted a three-dimensional finite element analysis of interior beam-column specimens with orthogonal beams under bilateral load, and of planar frame specimens under unilateral load. Comparisons were made between finite element modelling and experimental results and analytical investigations of stress conditions using bond characteristics of beam/column reinforcement and structural frame types as analytical parameters. The internal stress states, which are difficult to understand from laboratory testing, were investigated. The simulated stiffnesses were somewhat high compared with experiment results, but the maximum strength correlated well with the experiment. By examining compressive principal stress fields for diagonal cross sections, the authors show that the compressive strut region is big for test specimens with bonded interfaces, the strut region is narrower for specimens without bonded interfaces, and regions that do not carry stress exist. Distribution of shear stress within joints was shown for planar frame and interior beam-column joint specimens, and differences between specimens with and without bonded interfaces were investigated.