单压下多裂隙类岩材料的破坏特征及其影响因素(英文)

Failure characteristics and its influencing factors of rock-like material with multi-fissures under uniaxial compression

在伺服控制单轴加载试验机上,对采用养护前期拔出预埋金属插片方式制作的闭合多裂隙类岩试件进行压缩实验,研究裂隙倾角及裂隙分布密度对裂隙体破坏特征的影响机制。结果表明:裂隙倾角是影响裂隙体破坏模式的主要因素,受裂隙倾角的影响,裂隙尖端微裂纹呈现出不同的发育形态;而裂隙分布密度对裂隙体破坏模式的影响是通过影响裂隙贯通方式实现的。滑动裂纹模型表明:裂隙面上的有效剪力是裂隙面相对错动的驱动力,它是裂隙倾角与裂隙面摩擦因数的函数,这与实验所得结论相吻合。基于相同实验条件下类岩石材料的力学参数,建立了裂隙体的应变软化模型,并对实验结果的可靠性进行了验证。

The compression test on rock-like specimens with prefabricated closed multi-fissures made by pulling out the embedded metal inserts in the precured period was done on the servo control uniaxial loading instrument. The influence of fissure inclination angle and distribution density on the failure characteristics of fissure bodies was researched. It was found that, the fissure inclination angle was the major influencing factor on the failure modes of fissure bodies. The different developmental states of micro-cracks would appear on specimens under different fissure inclination angles. However, the influence of fissure distribution density on the failure mode of fissure bodies was achieved by influencing the transfixion pattern of fissures. It was shown by the sliding crack model that, the effective shear, which drove the relative sliding of the fissure, was a function of fissure inclination angle and friction coefficient of the fissure surface. The strain-softening model of fissure bodies was established based on the mechanical parameters that were obtained by the test of rock-like materials under the same experimental condition. And the reliability of experimental results was identified by using this model.