土-岩混合边坡的破坏模式研究  

Study on Failure Mode of Soil-rock Composite Slope

作　　者：张宝龙[1,2] 范文 ZHANG Bao-long;FAN Wen(School of Geological Engineering and Surveying, Chang＇an University, Xi＇an Shaanxi 710054, China;Inner Mongolia Transport Design and Researeh Institute Co. , Ltd. , Huhehot Inner Mongolia 010010, China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710064 [2]内蒙古交通设计研究院有限责任公司,内蒙古呼和浩特010010

出　　处：《公路交通科技》2018年第4期33-39,共7页Journal of Highway and Transportation Research and Development

基　　金：交通运输部西部交通建设科技项目(200631800006)

摘　　要：结合力学分析和极限分析中的上限定理,推导出了存在张性裂缝时边坡维持自稳的极限高度,对边坡发生滑坡、崩塌破坏的条件进行了理论界定。在此基础上,以实际工程中遇到的某土-岩二元结构边坡为研究对象,借助有限元方法对坡角、坡高影响下边坡的破坏模式进行了分析。研究发现:在土-岩接触面产状一定的情况下,坡角是边坡破坏模式变化的控制因素,坡高对破坏模式的影响则不是很明显,符合实际规律;对于本研究中边坡实例,当坡角在65°左右时是其发生滑坡、崩塌破坏的理论界限,小于此坡角时可能的破坏模式以滑坡为主,大于此坡角时发生崩塌破坏概率增加;当保持坡度在65°时,坡高的变化对坡体内拉应力发展深度及分布状态的影响很小,边坡的破坏模式还处于滑坡破坏与崩塌破坏的临界点附近。本研究的研究成果可为类似边坡的稳定性和破坏模式研究提供思路和理论支持。We derived the critical height for slopes with tension crack to keep stable by combining the mechanical analysis with upper bound theorem of limit analysis,and theoretically defined the condition for landslide or collapse of slopes. On this basis,we analyzed the effects of slope angle and slope height on failure mode of a soil-rock dual structure slope in practical engineering. The result shows that（1） the slope angle is the controlling factor on slope failure mode when the soil-rock interface occurrence keeps constant,whereas the impact of slope height on failure mode is not obvious,which is coincident with the objective rule;（2） for the subject slope,65° is the theoretical limit of slope angle for landslide and collapse,landslide will be the main failure mode when the slope angle is less than this value,otherwise the collapse probability will increase;（3） when the slope angle keeps at 65 °,the depth and the distribution of tensile stress are not sensitive to the slope height variation,the failure mode of the slope keeps near the critical state between landslide and collapse. The finding in this research can provide idea and theoretical support for studies on the failure mode and stability analysis on similar slopes.

关 键 词：道路工程 破坏模式 上限定理 土-岩混合边坡 坡度 坡高 

分 类 号：U416.14[交通运输工程—道路与铁道工程]