类岩石材料压缩破坏力学特性及裂纹演化特征

1.西安科技大学 安全科学与工程学院,陕西 西安 710054; 2.教育部 西部矿井开采及灾害防治重点实验室,陕西 西安 710054

预制裂隙; 类岩石材料; 压缩破坏; 声发射定位; 裂纹演化

Mechanics and crack evolution characteristicsof rock-like material under compression failure
LI Shu-gang1,2,CHENG Xiao-yu1,2,LIU Chao1,2

(1.College of Safety Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China; 2.Key Laboratory of Western Mine Exploration and Hazard Prevention,Ministry of Education,Xi'an 710054,China)

prefabricated crack; rock-like material; compression failure; AE location; crack evolution

DOI: 10.13800/j.cnki.xakjdxxb.2017.0601

备注

为探究含预制裂隙类岩石材料压缩破坏的力学特性及裂纹演化特征,利用自主研发的YYW-Ⅱ应变控制式无侧限压缩仪及高精度声发射(AE)监测系统,研究了含不同宽度预制裂隙的类岩石材料试样在单轴压缩条件下的受力变形和破坏模式,探究了试样的裂纹演化过程,进而分析了预制裂隙宽度对类岩石材料破坏的影响规律。结果 表明:预制裂隙宽度由3 mm增大到5 mm时,试样的峰值强度减小,峰值轴向应变增大,压密阶段的应变量亦增大; 试样的破坏模式由自身材料性质为主导的剪切破坏,转变为预制裂隙下半部区域张拉破坏诱发的剪切破坏; 试样主要裂纹演化由沿预制裂隙面向顶部和下部的发展,转变为预制裂隙下半部区域发育裂纹向上部和底部的扩展。研究成果可为岩土工程相似材料模型破坏特征及裂隙演化的研究提供一定的参考。

In order to study the mechanics and crack evolution characteristics of rock-like material with prefabricated crack under compression failure,self-developed YYW-Ⅱstrain controlled unconfined compression apparatus and high precision acoustic emission(AE)monitoring system were used to explore load and deformation characteristics,failure forms and crack evolution process of rock-like material samples with different width of prefabricated crack,then theinfluential law of width on failure of rock-like material was analyzed.The results show that when the width of prefabricated crack increases from 3 mm to 5 mm,peak intensity decreases,peak axial strain increases,and strain of compaction stage also increases; when the width of prefabricated crack is 3 mm,failure mode of thesample is mainly shear failure led by its own material properties,prefabricated crack basically has no effect on the failure of sample,with the increase of width,the failure form of sample changes from shear sliding failure along the prefabricated crack surface to shear failure induced by tension failure of prefabricated crack; Main cracks evolution of the samples develops from the lower area of the prefabricated cracks to the upper and bottom part.Research results could provide certain references for the study of failure characteristics and cracks evolution of similar material model in geotechnical engineering.