在伺服控制单轴加载试验机上,对采用养护前期拔出预埋插片方式制作的含2条贯通裂隙类岩石试件进行压缩试验；基于滑动裂纹模型理论,并结合试件破坏全应力-应变曲线和贯通破坏面颗粒体破坏形态分析裂隙试件断裂破坏机理.滑动裂纹模型表明:驱动裂纹相对错动的有效剪力是裂隙倾角α和裂隙面摩擦因数f的函数.试验中发现:裂隙试件发生破坏时,依据裂隙倾角和岩桥倾角的不同,将会出现单裂隙微裂纹贯通破坏、预制裂隙贯通破坏和无微裂纹发育的脆性破坏:根据裂隙试件岩桥区受力特征的不同,预制裂隙发生贯通破坏时,将呈现拉伸破坏、剪切破坏和拉剪复合破坏3种模式,岩桥区贯通面上颗粒体破坏形态随之依次呈现无摩擦、完全摩擦和部分摩擦痕迹.%The compression test on rock-like specimens with two prefabricated transfixion fissures made by pulling out the embedded metal inserts in the procured period was done using the servo control uniaxial loading tester. Based on the sliding crack model, the fracture failure mechanism of the fissure body was analyzed combined with the stress-strain curve and the failure form of granule on the transfixion surface of the specimen. It was shown by the sliding crack model that: the effective shear, which drove the relative sliding, was a function of the fissure inclination angle (a) and friction coefficient (f) of the fissure surface. It was found during the test that: when the fracture failure of specimens occurred, according to the differences of the fissure and rock-bridge inclination angle, the transfixion failure of micro-cracks at the tip of the signal fissure, the transfixion failure of the prefabricated fissures and the brittle failure without micro-cracks would appear in turn on specimens; and according to the differences of the stress characteristics in the rock-bridge region, when the transfixion failure of fissures occurred, three forms would be shown: tension fracture, shear fracture and tension-shear combined fracture, and the failure forms of the granule on the transfixion surface in the rock-bridge region would present zero-friction, entire-friction and partial friction, respectively.
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