单轴加载下砂岩声发射特征的试验分析

Experimental Analysis of the Acoustic Emission Characteristics of Sandstone Specimens under Uniaxial Loading Tests

声发射是岩石材料发生变形破坏时所伴随的一种普遍现象。在刚性试验机上,单轴受压条件下对砂岩破坏全过程进行了声发射试验,得到了砂岩破坏过程中的应力特征与时间、应变,声发射特征与时间、应变之间的关系曲线。通过对关系曲线的研究,着重探讨了声发射特征与应变之间的关系,并用拟合的方法得到了砂岩试样的近似破坏临界点,为0.9 x0,对砂岩破坏的监测预报具有一定的理论指导作用。

Acoustic emission（AE） is a ubiquitous phenomenon associated with deformation and failure of rock material.Experiments on AE characteristics of full-regime sandstone failure are conducted with a stiffness test machine under the condition of uniaxial compression.The relationships of stress characteristics with time-strain level and AE characteristics with time-strain level are obtained in the failure process of sandstone specimens.On the basis these results,the relationship of AE characteristic with strain level is discussed.The approximate critical point of the sandstone specimen is determined to be 0.9 through the curve fitting method.This study provides theoretical guidance to the monitoring and prediction of sandstone behavior.