基于DRA的应变差—应力曲线转折点辨识可靠性研究  

Discussion on Methods of Improving Measurement Precision of Deformation Rate Analysis Method

作　　者：梅志恒[1] 石凯 张俊思 毛勇 MEI Zhi-heng;SHI Kai;ZHANG Jun-si;MAO Yong(Faculty of Engineering,China University of Geosciences,Wuhan 430074,China;Wuhuan Engineering Co.,Ltd.,Wuhan 430074,China;Daye Nonferrous Metals Co.,Ltd.,Huangshi 435000,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]中国五环工程有限公司,湖北武汉430074 [3]大冶有色金属有限责任公司丰山铜矿,湖北黄石435000

出　　处：《世界有色金属》2020年第18期182-184,共3页World Nonferrous Metals

基　　金：中国地质大学(武汉)教学实验室开放基金资助项目(SKJ2016083)。

摘　　要：本文通过某金属矿山深埋大理岩试样的等幅循环加载和分级循环加载实验,实验结果表明:岩石存在两类非弹性变形,第I类是由加载应力未超过岩石之前所受最大应力σm时岩石局部单元的损伤所致;第II类是由加载应力超过σm时岩石内部微裂纹的产生或扩展所致;第II类非弹性变形与岩石应力记忆的形成密切相关。岩石记忆的是裂纹最大尺寸,当加载应力超过σm使得裂纹尺寸发生改变,原应力记忆将被抹去而形成新的应力记忆。DRA法用于地应力测量时,宜采用后续测量加载循环与首次测量加载循环之间的应变差–应力曲线进行分析,从而能够有效辨识DRA曲线转折点。In this paper,the experimental results show that there are two types of inelastic deformation of marble samples in a metal mine.The first type is caused by the damage of local elements of rock when the loading stress does not exceed the maximum stressσm;the second type is caused by the formation or propagation of microcracks in the rock when the loading stress exceedsσm;The second kind of inelastic deformation is closely related to the formation of rock stress memory.When the loading stress exceedsσm,the original stress memory will be erased and a new stress memory will be formed.When DRA method is used for in-situ stress measurement,the strain difference stress curve between the subsequent measurement loading cycle and the first measurement loading cycle should be used for analysis,so as to effectively identify the turning point of DRA curve.

关 键 词：变形率分析 辨识方法 变形记忆效应 

分 类 号：TG139[一般工业技术—材料科学与工程]