顺层岩质边坡静力开挖物理模拟试验研究

Physical excavation test research on a bedding rock slope

利用大型室内模型试验,开展了含软弱夹层顺层岩质边坡的静力开挖试验,试验结果表明:随着开挖角度的增大,边坡完成开挖卸荷松弛的时间大幅缩短。开挖角度为47°时,边坡位移稳定时间为214.56 h;开挖角度为60°和72°时,边坡位移稳定时间缩减为107.28 h。随着开挖角度增大,坡面位移稳定值逐渐增大,且位移稳定值随着高程的增加而增大。通过布设于坡体内部的位移传感器可以获得边坡在开挖过程中坡内及坡面的位移场,分析不同高程水平参考线处坡体位移分布曲线,并结合位移限制值可以得到边坡开挖位移松弛区范围。通过试验研究发现,含软弱夹层顺层岩质边坡开挖松弛区范围随着开挖角度的增大不断向坡脚和坡顶延伸,开挖松弛区范围增大。

A bedding rock slope with weak intercalated layers is a common kind of engineering geologic body in the engineering field. A large scale model experiment was proceeded to simulate the excavation of the bedding rock slope with weak intercalated layers. The test results show that with the increasing excavation angle,the unloading relaxation time of excavated slope will significantly shorten. When the excavation angle is 47°,the needed time for the displacement stability is 214. 56 h. When the excavation angle is 65° and 72°,the needed time for the displacement stability decreases to 107. 28 h. The displacement stable values increases gradually,and the displacement stable values increase with the increasing height. The displacement field of the bedding rock slope under excavation can be obtained by the displacement sensors in the slope body, and the displacement distribution curves at different heights are analyzed and the displacement limit value are combined to obtain the displacement excavation relaxation zone. The displacement excavation relaxation zone of the bedding rock slope with weak intercalated layers extend towards the toe and top of slope with the increasing excavation angle,and the displacement excavation relaxation zone will be bigger and bigger.