POLY-LINEAR APPROXIMATION ANALYSIS OF TENSION SOFTENING DIAGRAM FOR CONCRETE

Abstract

The tension softening diagram provides valuable informations to discuss the fracture behavior of concrete. In this paper, the numerical analysis method to calculate the poly-linear tension softeing diagram is investigated. The prediction method for the load-displacement relationships of concrete with cracks is developed by using the fictitious crack model concept with the K-superposition method and the constitutive law by the poly-linear tension softening diagram. In this method, nonlinear crack equations are solved by the iteration program of evaluating the softening inclinations. Poly-linear approximation method for calculating the softening diagram from the actual load-displacement curve is proposed based on the crack equation analysis method. The softening diagrams of concretes with various aggregates and matrix strengths are measured and their characteristics are'discussed.