再生混凝土疲劳损伤机理的数值模拟

基于再生混凝土内部细观结构的数字图像,建立了二维细观再生混凝土疲劳损伤有限元模型。首先,对弯折疲劳破坏后的再生混凝士弯折疲劳试件进行机械切割并对切割后的表面使用数码相机拍摄,获得截面数字图像。然后,对所获得的数字图像进行处理并对骨料和砂浆部分进行边缘检测,获得骨料和砂浆的边缘坐标,将其导入有限元分析软件,获得实体模型。最后,建立了二维细观再生混凝土疲劳损伤有限元模型,研究了再生混凝土在疲劳荷载作用下的损伤分布和应力分布的变化规律。

Numerical simulation on the fatigue damage mechanism of recycled concrete

Based on the digital image of the internal microscopic structure of the recycled concrete，a 2-D microscopic finite element model of the recycled concrete fatigue damage is established. Firstly，the recycled concrete specimen after bending fatigue damage is mechanically cut and then the digital image of the cutting-surface is made by digital camera. Subsequently，the digital image is processed along with the edge detection made on the aggregate and mortar，from which the edge coordinates of both the aggregate and the mortar are obtained and then imported into ANSYS development tools UPFs for getting the relevant solid model. Finally，a 2-D microscopic finite element model of recycled concrete fatigue damage is established，and meanwhile，the damage distribution and the variation law of the stress distribution under fatigue load are studied as well.