激光散斑法对冻土微裂纹形貌和发展过程的研究  

Study of appearance and development procedure of microcrack of frozen soil using laser speckle method

作　　者：梁承姬 李洪升[1] 刘增利[1] 孙秀堂[1] 朱元林[2] 

机构地区：[1]大连理工大学工程力学系 [2]中国科学院兰州冰川冻土研究所冻土工程国家重点实验室

出　　处：《大连理工大学学报》1998年第2期152-156,共5页Journal of Dalian University of Technology

基　　金：国家自然科学基金;冻土工程国家重点实验室资助项目

摘　　要：将激光散斑法用于冻土材料，得出了裂纹尖端存在一个微裂纹损伤区（或称为断裂过程区）的结论．通过对裂纹尖端一系列散斑图的逐点分析，绘出了微裂纹区随载荷增加而发展的形貌及其全过程，测定了裂纹嘴张开位移的临界值δＣ，从而为冻土材料的宏微观力学行为研究及弹塑性断裂韧度测试分析提供了有效的途径．Using laser speckle method on frozen soil, the authors have drawn a conclusion that a microcrack region, which can be named as fracture procedure region, exists on crack tip region. Through analysis on series of crack tip development figures, this paper illustrates the micro crack appearance and development procedure along with loading increase. At last, the authors figure out the critical value of crack tip opening displacement, and an efficient method is given for macro and micro mechanics behavior and elastoplastic fracture toughness test study for frozen soil.

关 键 词：散斑法 激光 冻土 裂纹张开位移 微裂纹区 

分 类 号：P642.14[天文地球—工程地质学] O348.1[天文地球—地质矿产勘探]