淮南孜矿红砂岩的非弹性变形柔度比探究

Determination of the Ratio of Anelastic Strain Recovery Compliance of Red Sandstone Retrieved from the Coalmine in Huainan

非弹性应变恢复法(ASR法)是目前常用的深部地应力测试方法,通常用该法进行地应力解算时需要假设其中一个重要的物理参数柔度比为0. 5。对非弹性应变恢复法的原理进行概述,并对淮南孜矿所取的红砂岩进行非弹性应变恢复试验,最后从两种原理入手求解其柔度值(体积变形柔度)、剪切变形柔度及最终柔度比(体积变形柔度/剪切变形柔度)。基于蠕变试验数据,通过流变理论分析,发现卸荷过程中岩石的扩容过程将引起柔度比参数的变化,其变化程度受卸载应力水平及岩石种类影响,因此柔度比取0. 5并不客观。ASR法若要用于实际工程还需要明确一些细观参数间的关系。

The anelastic strain recovery(ASR)method is the common used technique to determine deep field stress.The compliance ratio,which is the one of the most important parameters is usually assumed to be 0.5 in recent years during determining the magnitude of the in-situ stress.The basic principle of the ASR is described here and the laboratory experiments were performed on the red sandstone which were retrieved from the coalmine in Huainan.The values of compliance in volumetric mode and shear mode,and the ultimate compliance ratio of them from two different methods were investigated.And finally,by theoretically analyzing the rheology data,which concluded that the ratio of compliance will vary with the dilatation of stone,and the degree will be influenced by the unloading stress and species of stone.Thus,the conclusion that ratio is equal to 0.5 is not objective.More specific relationship between the micro parameters should be investigated if the ASR should be used in the real projects.