﻿ 混凝土断裂模量的尺寸与强度效应

# 混凝土断裂模量的尺寸与强度效应 Effect of Size and Strength Grade on the Concrete Modulus of Rupture

In this paper, the flexural strength of plain concrete beams subjected to three-point bending was numerically studied using the finite element program DIANA. Instead of using a discrete crack model, a smeared crack model is adopted in the numerical simulation. A non-linear tension softening curve was used to model the gradually diminishing tensile strength of concrete upon further crack opening. The factors influencing the flexural strength of plain concrete beams considered in this paper are the concrete strength grade and the beam depth. These two factors can be combined into one material parameter and the brittleness index. A relationship between the ratio of flexural strength to the tensile strength and the brittleness index was proposed based on the numerical results.

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