开挖与卸载交替作用对上陡下缓型高陡层状岩质边坡变形失稳影响试验研究  

Experiment of Alternating Actions of Excavation and Unload Effects on Deformation and Instability of High and Steep Bedding Rock Slopes with Upper Steep and Lower Gentle Style

作　　者：杨志全[1,2,3] 张震[1] 侯克鹏[1] 杨溢[1] 肖慧[1] 杜俊[1] 程涌 杨八九 

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]云南亚融矿业科技有限公司,云南昆明650093 [3]山西省交通科学研究院黄土地区公路建设与养护技术交通行业重点实验室,山西太原030006

出　　处：《四川大学学报（工程科学版）》2016年第6期8-15,共8页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(41071058;41402272);云南省应用基础研究计划项目资助(2015FB122);云南省省级人培项目资助(KKSY201421016);云南省教育厅科学研究基金重点资助项目(2014Z031);黄土地区公路建设与养护技术交通行业重点实验室开放基金项目资助(KLTLR-Y13-24)

摘　　要：以云南磷化集团有限公司所属尖山磷矿上陡下缓型高陡层状岩质边坡为工程背景,依据相似理论开展模型试验研究,分析开挖与卸载交替作用对这类型岩质边坡变形失稳的影响。结果表明:上陡下缓型高陡层状岩质边坡随开挖深度的逐渐增加,其对应的位移变形量也逐步变大,边坡整体上表现为上部向下运动,下部受压向临空面方向隆起的变形规律;同时当开挖至一定的深度后,坡面与坡中均会发育较多的走向裂缝,且随着开挖深度的不断增加,其不断向坡体深部延伸发展。在整个开挖过程中,坡体中会发育形成"平面与圆弧面复合型的潜在最危险滑移面,且表现为滑移-弯曲-剪切的变形失稳破坏特征。对边坡开展的浅部卸载作用效果不理想,虽其位移变形量有所减小,但没有改变坡体整体的变形失稳趋势,对边坡施加的深部卸载作用效果非常明显,使坡面及坡顶产生的裂缝几乎完全消除。研究结果可为中国西部大开发过程中面临的上陡下缓型高陡层状岩质边坡的预警预报与治理设计提供参考。Alternating actions of excavation and unload have a very important influence on the deformation and instability of high and steep bedding rock slopes with upper steep and lower gentle style,which are widely distributed in China＇ s western regions. Taken the high and steep bedding rock slopes belonging to Jianshan phosphorite mine, Yunnan phosphate group Co. , Ltd as an engineering background, model experiment was conducted on the basis of similarity theory, and alternating actions of excavation and unload effects on their deformation and instability were investigated. Research results showed that the deformation displacements of high and steep bedding rock slopes with upper steep and lower gentle style progressively become larger with the gradual increase of the depth of excavation. Its integral deformation laws are that upper slope moves downward, while lower part uplift to the free surface due to compression. At the same time, when the excavation is to a certain depth, many strike cracks can be developed into the slope, then they continuously extend to the slope body in pace with increasing excavation depth. During the whole process of excavation, potentially most dangerous slip surface of composite-style with plane and circular ayc surface is developed gradually into the slope, and deformation and instability characteristics of slip-bending-shear style appear. Although the deformation of the slope is reduced, the trend of deformation and instability of slope is not changed, so the shal- low unloading effect is not ideal, while deep unloading effect is very obvious and cracks in the slope are almost completely eliminated. Research achievements play a reference guiding role for early warning and forecast and control design of high and steep bedding rock slopes.

关 键 词：开挖与卸载交替作用 上陡下缓 高陡层状岩质边坡 相似模型试验 

分 类 号：TU454[建筑科学—岩土工程]