不同加载速率下木材失效行为的多尺度数值分析  

Multi-scale numerical analysis on failure behavior of wood under different speed loading conditions

作　　者：钟卫洲[1] 邓志方[1] 魏强[1] 陈刚[1] 黄西成[1] ZHONG Weizhou DENG Zhifang WEI Qiang CHEN Gang HUANG Xicheng(Institute of Systems Engineering,China Academy of Engineering Physics,Mianyang 621999,China)

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621999

出　　处：《中国测试》2016年第10期79-84,共6页China Measurement & Test

基　　金：国家自然科学基金(11302211;11390361;11472257;11572299)

摘　　要：基于云杉微观结构特征,建立代表体积元模型,对顺纹和横纹压缩下云杉大变形行为进行数值模拟,获得材料各向异性和宽平台应力特性。数值模拟涉及准静态、5,50,500 m/s 4种加载速率,结果表明剪切滑移和屈曲塌陷是木材顺纹压缩的主要失效模式;横纹压缩则体现为胞墙褶皱和循序塌陷。加载速率对顺纹压缩影响高于横纹方向加载,高速加载时木材在轴向压缩下呈现花瓣形破坏,而横纹压缩则表现为压缩膨胀断裂;相对于高速加载,低速加载下木材变形表现为更均匀、平稳。Based on spruce microstructure characteristic, representative volume element model of spruce cell is established. Large deformation of wood in axial and transverse compression is simulated in the study. Spruce orthotropic and wide range stress plateau behavior is described. Numerical simulations of several loading velocities, quasi-static, 5m/s, 50m/s and 500m/s, are performed to analyze loading rate influence on wood microstructure deformation. The results show shear sliding and buckling collapse are the main failure modes for wood axial quasi-static compression. Transverse compression is with cell wall folding and gradual collapse. Loading velocity has a greater influence in axial compression than transverse compression. High loading velocity induces wood petal failure in axial compression. On the contrary, impact end is with expanding fracture for transverse loading. Comparing with high velocity compression, deformation is obviously stable and uniform in low velocity compression process.

关 键 词：云杉 多尺度模型 代表体积元 数值模拟 

分 类 号：TU375[建筑科学—结构工程]