基于PFC2D不同细观参数对生态混凝土宏观破坏分析

采用PFC2D离散元软件通过内嵌的Fish语言创建了不规则骨料,通过建立的生态混凝土数值模型利用控制变量法从不同细观力学参数对其双轴压缩破坏的影响进行了分析。研究结果表明:平均强度和标准差主要影响混凝土材料的不均匀性,不均质度越高,强度越低,裂纹空间分布越分散;摩擦系数主要影响应力应变曲线的形状和材料强度,摩擦系数越大,颗粒之间的咬合力越大,曲线下降段的残余强度也就越大;刚度比值和接触模量的增大均会造成颗粒之间形成刚性接触,平行黏接的作用会被削弱导致高抗拉应力和更多的张拉裂纹,最终宏观表现为张拉破坏。对混凝土数值模型的力学细观参数进行探究能够更好地对其进行参数的选择,为以后建立数值模型提供参考依据。

The analysis of the macro failure for ecological concrete based on PFC2D different mesoscopic parameters

The fish language embedded within PFC2D is used to create irregular aggregate, the numerical model that what we create is analyzed via Using the method of control variables for the influence of biaxial compression failure. The results show that : the main influence of concrete material inhomogeneity is the mean intensity and standard deviation, the higher inhomogeneous degree the lower intensity and the crack space distribution become more disperse; Friction coefficient is the main influence for the shape of stress-strain curve and material intensity, the higher friction coefficient , the greater the bite force between the particles, the greater the residual strength of the curve decline; The formation of rigid contact between particles is caused by the increase of stiffness ratio and connect modulus ,the effect of parallel bond is weaken and high tensile stress and more tension crack are produced , eventually macro performance come from tension crack. It can be helped us make a better choice by studying the mesoscopic mechanics parameters of the concrete numerical simulation and provided the basic reference for building numerical model later.