卸荷裂隙岩体在桥基荷载作用下的力学行为研究

Mechanical Behavior of Rock Mass near Unloading Crack Under Load

为研究卸荷裂隙附近岩体在桥基荷载作用下的力学行为,在分析桥基和岩体相互作用以及裂隙模拟方法的基础上,建立了二维有限元模型,分析卸荷裂隙不同的深度和倾角下,裂隙表面的位移和应力影响系数变化情况。结果表明:桥基荷载下,裂隙表面的位移以竖向位移为主;应力影响系数随着裂隙深度先增加后减小,最后趋于固定值;卸荷裂隙倾角达到90°时,应力影响系数急剧增大,这说明竖向裂隙对边坡的应力影响最大。

To study the mechanical behavior of rock mass near the stress-release crack under bridge foundation load,a two-dimensional finite element model was developed based on fracture simulation method and the analysis of the interaction between rock mass and the bridge foundation. Then the model was used to calculate the displacement and stress influence coefficient changed with different depth and stress-release crack angle. The results show that the vertical displacement is the main displacement of the fracture surface and the stress influence coefficient increases initially and then decreases with the changing of depth,and finally reaches to a fixed value under the bridge foundation load. When the angle of the tress- release crack reaches 90°,the stress influence coefficient increase sharply which means the vertical crack has the major impact on slope stress.