CAJ | 학술논문

为了研究花岗岩脆性破坏特征和机制，进行不同围压下的三轴压缩试验，并对花岗岩破裂面断口进行电镜扫描测试，分析不同围压下花岗岩断口的微观形貌特征，最后讨论花岗岩脆性破坏机制。试验结果表明：在研究的围压范围内，花岗岩表现为典型的脆性破坏，随围压升高未出现脆-延转换特征；围压作用下除倾斜剪切破坏面外，还有“Y”型破坏形态；峰值前有无塑性变形产生以及发生塑性变形的范围和程度是决定花岗岩发生脆性破坏的主要原因，而岩石矿物成分和微观结构的差异性是其内在机制；峰值后应力降的大小和速度是花岗岩脆性破坏程度的外在表现，宏观裂纹的贯通速度决定峰值后应力降大小，岩体内积聚的能量大小是造成裂纹贯通速率快慢差异的内在因素，宏观断裂面是否完全贯通是应力降大小的决定因素。
위료연구화강암취성파배특정화궤제，진행불동위압하적삼축압축시험，병대화강암파렬면단구진행전경소묘측시，분석불동위압하화강암단구적미관형모특정，최후토론화강암취성파배궤제。시험결과표명：재연구적위압범위내，화강암표현위전형적취성파배，수위압승고미출현취-연전환특정；위압작용하제경사전절파배면외，환유“Y”형파배형태；봉치전유무소성변형산생이급발생소성변형적범위화정도시결정화강암발생취성파배적주요원인，이암석광물성분화미관결구적차이성시기내재궤제；봉치후응력강적대소화속도시화강암취성파배정도적외재표현，굉관렬문적관통속도결정봉치후응력강대소，암체내적취적능량대소시조성렬문관통속솔쾌만차이적내재인소，굉관단렬면시부완전관통시응력강대소적결정인소。
In order to study the characteristics and mechanism of brittle failure of granite,the triaxial compression tests under different confining pressures were conducted and the scanning electron microscopy(SEM) were carried out. The microscopic characteristics of failure surface and the brittle failure mechanisms were discussed. In the range of the confining pressures adopted in the experiment,the granite showed strong characteristics of brittle failure and had no brittle-ductile transition. In addition to the oblique shear failure fracture,a kind of Y-shaped failure surface also appeared. The brittle failure of granite is governed by the occurrence of the plastic deformation and the scope and extent of the plastic yielding during the pre-failure period. The different mineral compositions and microscopic structural differentiations are the internal mechanism of brittle failure. The magnitude and the speed of the stress drop during the post-failure period are the external manifestations of the intensity of the brittle failure of granite. The speed of post-failure stress drop is determined by the interconnecting speed of macroscopic fractures which depends on the energy accumulation in granite. Whether the macroscopic fractures are interconnected completely determines the magnitude of post-failure stress drop.