【摘要】 为研究硬脆性岩体的卸荷流变力学特性,以大岗山水电站坝区为依托,经过现场采样取芯,采用三轴流变试验机,开展硬脆性辉绿岩不同应力路径下的三轴流变试验研究。研究结果表明:卸荷流变和加载流变都存在门槛效应;加载流变破坏的侧向应变为轴向应变的2~3倍,卸荷流变破坏时为1~7倍;加载流变破坏形态主要为剪切破坏,而卸荷流变破坏形态主要为劈裂破坏;轴向应力σ1恒定卸围压流变时岩样表现出的脆性比偏应力(σ1-σ3)恒定卸围压流变更为剧烈;二者的流变破坏破坏强度均比常规三轴强度低。更多还原

【Abstract】 In order to study the unloading rheological mechanical properties the triaxial rheological tests of hard brittle diabase in different stress paths were carried out by using triaxial rheological testing machine. The diabase specimens used in the tests were all from field sampling in Dagangshan dam side. The results indicate that threshold effect exists both in the unloading confining pressure rheological tests and the triaxial loading rheological tests. The ratio of the lateral strain and axial strain is 2 to 3 in the triaxial loading rheological tests, while it is 1 to 7 in the unloading confining pressure rheological tests. The diabase specimens are all showing brittle failure in unloading and loading rheological tests,and the failure pattern in triaxial loading rheological tests is mainly in the form of shear failure while it is the split failure in unloading confining pressure rheological tests. The brittle characteristics of constant σ1 are stronger than those of constant σ1-σ3 in unloading confining pressure rheological test, and the long-term rheological strength of the two forms is lower than that of the conventional triaxial rheological.更多还原