Drucker-Prager型構成則を用いた円柱コンファインドコンクリート供試体の圧縮破壊FEM解析

Abstract

Main purpose of the present study is to discuss the effect of parameters (e.g. internal friction angle and dilatancy angle) of the constitutive law of Drucker -Prager type on the result of simulation analysis of confined concrete under compression. Two series of 3-D FEM analyses have been carried out. Firstly, the optimum values of the internal friction angle and dilatancy angle, used in the Drucker-Prager type plasticity model with the strain softening effect, have been discussed for a set of compressive strength data of concrete specimens with different shapes. As a result, reasonable value as the internal friction angle has been found to be approximately 30 degrees for a condition of rather high equivalent lateral pressure. Secondly, simulation analyses have been carried out for the compressive behavior of cylindrical concrete specimens confined by steel tubes or reinforcing bars, introducing interface element and different values of the internal friction angle. As a result, it has been pointed out that the distribution of equivalent confining pressure along the longitudinal direction of a specimen and the progress of the degree of damage in horizontal sections differ to a large extent by the value of internal friction angle applied.