节理岩体边坡稳定性的锚杆支护影响分析

采用数值计算方法,建立了节理边坡的计算模型,探讨了结构面厚度对于节理边坡稳定性的影响,以及锚杆长度、倾角、间距与边坡安全系数的关系,得到:(1)随着结构面厚度的增大,安全系数先减小后增大。(2)锚杆长度的增加会引起边坡安全系数的增大;当锚杆长度增加到一定程度后,继续增加将无法提高安全系数。(3)随着锚杆长度的增加,边坡的破坏区域逐渐增大;继续增加锚杆长度,使锚杆整体长度超过结构面,边坡整体从沿结构面滑动转化为沿内部岩体发生滑动。(4)边坡安全系数随锚杆倾角的增大呈现先增大后减小的趋势;锚杆长度越长边坡整体安全系数对于锚杆倾角的灵敏度越大。(5)锚杆间距越大,边坡安全系数越小,二者呈现显著的非线性特征。

Influence of Bolt Reinforcement on Stability of Rock Jointed Slope

The calculation model of rock jointed slope was founded by numerical method, the influence of joint thickness on slope stability was analyzed, and the relationship of slope safety factor with bolt length, orientation and spacing was discussed. The analysis results show that (1) with the increase of joint thickness, the safety factor decreases at first and then increases; (2) the lengthen of the bolt will lead to the larger safety factor of slope, but when bolt length reaches some magnitude, the effect of bolt length  on safety factor is limited; (3) with the increase of bolt length, the failure zones of the slope will become larger, the continuous lengthening of bolt length which makes the bolt running through the joint plane will result in the failure mode of the whole slope changes from slipping along structure plane to internal rock mass; (4) the increase in the bolt orientation will lead to the first increase then decrease of safety factor, longer bolt can make safety factor more sensitive  to the bolt orientation; (5) safety factor of slope will decrease with increase of bolt spacing, whose relationship is nonlinear.