西南科大西部滑坡形成机制分析及稳定性评价

在西南科技大学新校区建设中,由于人工平整场地开挖而形成临空面,引起污染控制中心西部的滑坡发生。为确保污染控制中心的安全和工程治理提供设计依据,文章通过对滑坡区地形地貌、气象水文、地层岩性、地质构造及水文地质条件等地质环境的分析,以及基于滑坡体、滑面(带)、滑床及变形等特征的阐述,对其稳定性和形成机制做出了定性分析。结果表明:该滑坡的形成是在以岩土体物理力学性质、特殊的地形地貌条件为主控因素与以人工开挖坡脚、地下水及大气降水作用为诱发因素的共同作用下,致使该滑坡目前仍处于蠕滑变形阶段。另外,采用分段传递系数法对滑坡的稳定性进行了定量评价。结果为:天然状态下,整体稳定性相对较好,处于暂时稳定状态。但在滑坡前缘的次级地带仍处于缓慢活动状态。这与滑坡的现状基本相符,也使定性评价得到了验证。饱水状态下,稳定性系数大幅度下降,滑坡的稳定性差,表明在持续饱水或降雨的条件下发生斜坡整体失稳。同时,两种工况条件下的稳定性系数相差较大,说明滑带土的内摩擦角和粘聚力对稳定性系数影响较大,也提出了相应的治理措施。

Formation mechanism and stability analysis of the landslide in the west of Southwest University of Science and Technology

During the process of construction of new campus of Southwest University of Science and Technology, a landslide occurred in the west of the pollution control centre. In order to ensure the safety of the construction of Pollution Control Center and provide reference for engineering design, the authors analyzed the conditions of geological environment of the lands lide, including topography, weather, hydrology, stratum and lithology, geologic structure, and the ground water. Based on the basic character of landslide and its deformation features, the authors analyzed the formation mechanism of the landslide and its stability, and found that the landslide was induced by the excavation, controlled by poor mass property and groundwater conditions. Additionally, the authors analyzed the stability of landslide with sectional transfer coefficient method quantificationally. The result indicates that the slope is stable as a whole under natural state, but its foreside of landslide is still slowly moving, which conforms with actual state, and validates the legitimacy of qualitative assessment. However, under water-saturated state, the stability coefficient considerably decreases, stability of the landslide is very low, and holistic stability of slope will lose under the conditions of heavy rainfall. At the same time, stability coefficients change greatly under two conditions, showing that the ~ values greatly influence stability coefficient. At last, the authors put forward corresponding countermeasures.