玄武岩台地型滑坡灾害动态风险综合评价及防灾控制——以嵊州市剡湖街道南山塘滑坡为例  

Dynamic Risk Assessment and Disaster Prevention of Basalt Platform Landslide——A Case Study of Nanshantang Landslide in Shanhu Town,Shengzhou City

作　　者：徐兴华 吴雪琴 冯杭建 唐小明 卢琰萍 XU Xinghua;WU Xueqin;FENG Hangjian;TANG Xiaoming;LU Yanping(Zhejiang Institute of Geology and Mineral Resources,Hangzhou310007,China;Shengzhou Natural Resources and Planning Bureau,Shengzhou312400,China)

机构地区：[1]浙江省地质矿产研究所,浙江杭州310007 [2]嵊州市自然资源和规划局,浙江嵊州312400

出　　处：《安全与环境工程》2023年第1期140-154,共15页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(42277132、42230702);浙江省基础公益研究计划项目(LGF21D020001);浙江省重点研发计划项目(2021C03159);浙江省自然资源厅科技项目(2021-77);浙江省地质矿产研究所科技创新基金项目(ZD2020KJ05);2020年中央自然灾害防治体系建设补助资金项目。

摘　　要：嵊州市剡湖街道南山塘滑坡是典型的玄武岩台地型滑坡,结合该滑坡特征和成因机制分析,采用非饱和渗流和极限平衡分析理论,通过流固耦合数值计算和蒙特卡洛模拟手段,以风险评价技术为指导,建立降雨作用下滑坡稳定性-危险性-动态风险综合评价体系,并以不同降雨强度下滑坡灾害动态风险水平为准则,开展滑坡综合防灾决策研究,分析系统截排水和远程自动化监测预警等技术体系用于玄武岩台地型滑坡综合防治的可行性及效果。结果表明:该滑坡所处台地地貌、玄武岩间夹硅藻土分布以及潜在滑移面缓倾状产出构成特殊的滑坡地质结构特征,降雨及地表水入渗对滑坡体稳定性具有弱化和劣化作用,可引发坡体局部差异变形或剪切蠕滑,滑坡变形破坏模式属于蠕滑-拉裂式;在暴雨直至大暴雨和特大暴雨的作用下,滑坡由基本稳定发展为欠稳定,滑坡危险性渐变为中等危险性,滑坡危险区内综合风险等级为高和极高的范围相应扩大,动态风险水平变高则有必要加强滑坡风险管控;结合滑坡地质结构特征、动态风险水平以及场区环境和治理投入,采用系统截排水和远程自动化监测预警相结合的技术体系对南山塘滑坡进行综合防治,经监测分析和效果评价,治理工程的防治效果显著,滑坡目前处于稳定状态且危险性低,也证实该综合治理手段可作为玄武岩台地型滑坡防灾控制行之有效的技术方法。Nanshantang landslide, which is in Shanhu Town, Shengzhou City, is a typical basalt platform landslide.Based on the landslide characteristics and genetic mechanism analysis, a comprehensive evaluation system of landslide stability-hazard-dynamic risk under rainfall condition is established using unsaturated seepage and limit equilibrium analysis theory, through the fluid-structure interaction numerical calculation and the Monte Carlo simulation method, under the guidance of the risk assessment technology.The comprehensive disaster prevention decision of landslide is studied, based on the criteria of the landslide hazard dynamic risk level under different rainfall intensity.The reliability and treatment effect are analyzed concerning systematic water interception and drainage and remote continuous monitoring and warning technology system used in comprehensive prevention and control of basalt platform landslide.The results show that the terraced landscape, the basalt interspersed with diatomaceous earth distribution and potential sliding surface gently inclined output constitute the special geological structure characteristics, and the rainfall and surface water infiltration have weakening and deteriorating effects on slope stability, which can cause local differential deformation or shear creep.The deformation failure mode belongs to creep slip-cracking type.Under the action of rainstorm to severe rainstorm or extraordinary rainstorm, the stability of landslide will develop from basically stable to less stable, the risk will gradually become to medium level, and the high and extremely high range of the comprehensive risk level will be expanded accordingly.When the dynamic risk level becomes high, it is necessary to strengthen the control of landslide risk.Combined with the geological structure characteristics of landslide, dynamic risk level, site environment and treatment investment, the comprehensive prevention and control of Nanshantang landslide is carried out by the combination of systematic water interceptio

关 键 词：玄武岩台地型滑坡 降雨作用 动态风险评价 系统截排水 远程自动化监测预警 

分 类 号：X43[环境科学与工程—灾害防治] P642.22[天文地球—工程地质学]