岩石类材料振动裂隙扩展试验和数值分析

岩性体振动裂隙扩展是路基、桥梁、振动施工和防震等领域共同关注的问题。通过自制惯性加载装置联合振动实验台，对12组含边中穿透裂隙的板状相似岩样进行振动加载试验，观测裂隙扩展和贯通规律，并利用PFC颗粒流软件建立试验对应模型，进一步分析裂隙扩展的控制机制。结果表明，不同区域振动变形的相位差会促进裂隙的扩展行为；边裂隙的起裂方向与振动方向夹角较小，约在±10°以内，且与振向相同的边裂隙最容易扩展，与振向相同的边—中裂隙对最容易贯通；破坏频率与裂隙间距呈正相关性，并且随着裂隙倾角和振向夹角的增大，裂隙扩展越来越困难，垂直振向的裂隙最难扩展；振动裂隙扩展路径为裂尖最近路线，符合能量最小原理。

Test and numerical analysis of crack propagation caused by vibrations of rock materials

Crack propagation caused by vibration of lithosome is a common concern in the fields of subgrade, bridge, vibration construction and earthquake prevention etc. Through combining the home-made inertia loading device with the platform of vibration, we implement 12 groups of vibration loading experiments on similar rock plates with penetrating cracks, observing the propagation and coalescence mechanism. Moreover, we establish the corresponding model in PFC software to analyze mechanism of crack propagation further. The results show that the phase difference of vibration deformation in different regions promotes the crack propagation behavior. The dipping angle between the direction of vibration and the initial propagating direction of notches is a little bit small, within the scope of ±10 degrees. Besides, in the direction of vibration, the notch is easier to propagate; while the couple of notch-middle fracture is prone to coalesce. The frequency of crack collapse shows positively correlative to the crack spacing. With the increase of the dipping angle between the crack inclination angle and the vibration direction, crack propagation becomes more and more difficult; and it’s the most hardly when the crack is perpendicular to the vibration direction. The same as what in static process, the path of crack propagation by vibration is the nearest route, which is consistent with the minimum energy principle.