甘肃省东乡县下坪山滑坡特征及稳定性评价

黄土滑坡是西北地区人居与城镇建设安全的重大隐患，正确认识黄土滑坡的发育特征和形成机理，对于开展滑坡灾害风险评价、预测预警、工程治理及防灾减灾等方面具有重要的战略意义?为了保障黄土脆弱地区生态保护和高质量发展，解决滑坡在实现乡村振兴战略过程中对规划和建设的影响，本文在对甘肃省东乡县陈家下坪山滑坡进行地质勘察和现场调查的基础上，通过地面调查、钻探和探槽等多种手段，结合区域环境详细研究滑坡发育的特征，阐明了地形地貌、地层岩性、坡体结构、水文地质、大气降水和人类活动对滑坡的影响。运用定性分析与定量计算相结合的方法，系统分析评价了下坪山滑坡在不同工况下的稳定性。结果表明，下坪山滑坡为老滑坡整体复活，属于中型黄土—泥岩滑坡，其运动特征为间隙性下错的牵引式低速滑动，降雨和人类工程活动是该滑坡稳定性的敏感因素；滑坡目前处于基本稳定状态，受裂缝大量发育的影响，局部有发生滑动的可能性，但未来环境变化会导致滑坡整体滑移失稳的可能性大；依据滑体原始冲沟为界将下坪山滑坡分为东西两块，西侧整体稳定性好于东侧，东西两处滑坡块体在遇暴雨或地震沿现有滑面发生再次滑动的可能性较大。在西北内陆暖湿化的大背景下，该区黄土老滑坡存在复活的风险，应进一步加强相关的监测工作。

landslide characteristics; influencing factors; stability; Xiaping mountain landslide; Dongxiang County

Loess landslides are a major hidden danger to the safety of human settlements and urban construction in Northwest China. A correct understanding of the development characteristics and formation mechanism of loess landslides has important strategic significance for carrying out landslide disaster risk assessment, prediction and early warning, engineering treatment, and disaster prevention and mitigation. In order to ensure the ecological protection and high-quality development of the fragile loess area, and to solve the impact of landslides on planning and construction in the process of realizing the rural revitalization strategy, Based on the geological exploration and field investigation of the Xiaping mountain landslide in Chenjia, Dongxiang County, Gansu Province, Ground survey, Drilling and Trench were used to study the characteristics of landslide development in combination with the regional environment, and clarified the influence of topography, stratum lithology, slope structure, hydrogeology, precipitation and human activities on landslides. Using the methods of qualitative analysis and quantitative calculation, the stability of the landslide under different working conditions was systematically analyzed and evaluated. The results showed that the Xiaping mountain landslide was a whole resurrection of the old landslide and belongs to a medium-sized loess-mudstone landslide. Its movement is characterized by intermittent traction low-speed sliding. Rainfall and human engineering activities are sensitive factors for the stability of the landslide; the landslide is currently in basically stable state, affected by the large number of cracks, there is a possibility of local sliding, but future environmental changes will cause the overall instability of the landslide; According to the original gully of the sliding body, the Xiaping mountain landslide is divided into east and west blocks, The overall stability of the west side is better than that of the east side, The east and west landslide blocks are more likely to slide again along the existing sliding surface in case of heavy rain or earthquake. With the warm and humid inland of the northwest, the old landslides has the risk of resurrection, and related monitoring work should be strengthened.