苏州阳山东侧滑坡变形对下部采空区的响应分析

Response analysis of deformation to front goaf of eastern side landslide of Yangshan in Suzhou

为了查清苏州阳山东侧消防通道地表变形和开裂的原因,现场钻探取凝灰岩样品进行测试,并在现场布置地表位移监测点30个、路面沉降监测点13个、深部水平位移监测点4个,对山体变形进行监测。监测结果表明,自2021年11月至2022年5月,山体表面最大位移超过80 mm,位移速度为0.5 mm/d,且地表各点位移速率不同,岩土体变形不协调,易导致岩土体破坏或滑坡事件发生。深部位移监测结果表明:山体中发生水平位移的岩体深度超过30 m,最大深部位移达14 mm;结合气象数据分析认为,降雨入渗对边坡稳定性影响较小;山体稳定性主要受下部采空区塌陷影响,山体下部和坡顶有多处地表开裂和错动现象。目前山体变形正处于等速蠕变阶段,如不控制边坡变形,岩土体位移达到加速蠕变阶段后易发生灾变。数值分析结果表明:在山体位移和采空区范围不断增大作用下,若阳山东侧前缘塌陷持续扩大,将对山体稳定性产生较大威胁。研究成果对阳山地区采空区影响下滑坡稳定性分析和滑坡治理具有指导意义。

In order to find out the causes of surface deformation and cracking of the road on the eastern side of Yangshan mountain in Suzhou city.Boreholes were drilled and some tuff samples were taken.About 30 points for surface displacements,13 points for pavement settlement and 4 points for deep horizontal displacements,were installed to monitor the mountain deformation.The monitored results show that,from November 2021 to May 2022,the maximum displacement of the surface was more than 80 mm,with the speed of 0.5 mm/d,and the speed of each point was different,which would lead to destruction of the rock mass or landslide.It showed that the thickness of rock mass with horizontal displacements in the mountain was more than 30 m,and the maximum value was 14 mm.According to the meteorological data,it was found that rainfall infiltration had little impact on slope.Affected by the collapse of the lower goaf,many surface cracks and dislocations at the lower part of the slope surface were found.The stability of the mountain is mainly affected by the collapse of the lower goaf.At present,the mountain deformation is in the constant speed creep stage.If the deformation is not controlled,it will be prone to catastrophes after reaching the accelerated creep stage.If the front collapse of the eastern side of Yangshan continues to expand,it will pose a greater threat to the stability of the landslide.The research results have guiding significance for the stability analysis and treatment for the landslide due to goaf in Yangshan.