圆柱形类断续节理试样制备及单轴抗压强度

Preparation Technology and Uniaxial Compression Strength of Cylindrical Rock-like Specimens with Non-persistent Joints

为研究节理间距、排距、倾角对断续节理试样单轴抗压强度和破坏模式的影响规律,研发了圆柱形类断续节理试样制备技术,并预制了45组不同排距、间距及倾角的类断续节理岩体试样。研究结果表明:在节理排距和倾角一定的情况下,类断续节理岩体单轴抗压强度随间距的增大而增大;断续节理排距为3 cm时,类断续节理岩体单轴抗压强度整体上随节理倾角增大而增大;断续节理排距为9 cm时,类断续节理试样单轴抗压强度与节理倾角呈现出"V"字形特征;断续节理排距为6 cm时,类断续节理岩体单轴抗压强度随节理倾角的变化规律不甚一致,表现出过渡特征;将类断续节理岩体破坏模式划分为类轴向劈裂破坏、既有断续节理端部翼裂纹扩展贯通破坏、既有节理端部产生新生裂纹与沿预制节理张开复合破坏和沿既有断续节理面的剪切滑动破坏四种类型。

In order to study on the influence of joint separation distance, row spacing and angle on the uniaxial compressive strength and failure mode of non-persistent joints, the cylindrical rock-like specimens with non-persistent joints preparation technology have been developed, and 45 groups of rock samples with different separation distance, row spacing and angle have been prefabricated. The results show: in the case of a certain row spacing and angle, the uniaxial compressive strength of rock-like specimens with non-persistent joints increases with the increase of separation distance. When the row spacing is 3 cm, the uniaxial compressive strength of the non-persistent joints increases with the angle. When the row spacing is 9cm, the uniaxial compressive strength of the non-persistent joints is “V” distribution with the change of the angle. When the row spacing is 6 cm , the uniaxial compressive strength of the non-persistent joint is not consistent with the change of the joint angle, and shows the transition characteristics. The failure modes of the rock-like specimens with non-persistent joints are divided into four types: axial splitting failure, crack propagation through failure at end wing of non-persistent joints, new cracks at the end of joints and a composite failure along the prefabricated joints, shear slip failure along existing non-persistent joint surfaces.