降雨诱发雅泸高速K198～K199段堆积层滑坡变形破坏特征及稳定性研究

发布时间：2018-01-21 16:50

本文关键词： 碎石土滑坡变形特征稳定性评价影响因素防治措施　出处：《西南交通大学》2016年硕士论文　论文类型：学位论文

【摘要】：雅泸高速位于四川省境内,是国家重要公路北京～昆明路段的重要组成部分。线路所经地区地形复杂,属于中山构造剥蚀堆积地貌,地层岩性分布多样,断裂构造发育。在此地质背景下,由于人类工程活动,诱发了大量的地质灾害。雅泸高速K198～K199段,在2009年9月中旬的一场连续强降雨过程后,路基和路肩挡墙发生明显变形,虽然当时即进行了工程加固,但在其后一年多的时间中,滑坡体的变形不断增长,破坏程度不断加剧,严重影响了雅泸高速的正常通行。本文的研究目标旨在通过现场调查滑坡体的工程地质条件和变形破坏的时间和空间分布特征,来分析滑坡体变形破坏规律和发生机理,进行滑坡稳定性分析与评价,并有针对性的提出治理措施建议。该滑坡为降雨诱发的碎石土边坡失稳形成,滑坡体物质组成为第四系的人工填土、中密～密实的块碎石土和可塑～软塑状态的粉质粘土。滑坡后缘出现在半挖半填路基的路面上。后缘公路的沉降变形和公路外侧的挡墙倾倒变形始于2009年9月,此时公路仍然处于施工过程中；且滑坡体所在的公路变形,在公路建成通车以后,依然在不断加剧,尤其是在暴雨过后。根据滑坡的变形程度将滑坡体分为三个区,变形最为明显的为滑坡体的中后部。将滑坡体的变形过程监测数据与相应时间段的降雨资料对比分析可得,虽然滑坡体的变形相对于连续降雨具有一定时间间隔的滞后效应,但毫无疑问滑坡体的变形是由降雨触发而引起的。另外,滑坡体松散的物质组成、内部丰富的地下水、公路施工荷载,是加剧滑坡体变形的重要因素。通过极限平衡法和数值模拟分析进行滑坡体在暴雨和天然状况的下的稳定性评价,结果表明：滑坡体在天然状况下保持基本稳定状态,在暴雨状态下处于不稳定或欠稳定状态；滑坡体最大位移处于滑坡体中后部。据此,本文提出了排水和支护双管齐下的措施控制滑坡体的变形。
[Abstract]:The Yalu Expressway is located in Sichuan Province and is an important part of the important national highway from Beijing to Kunming. The area through which the route passes is complicated in topography and belongs to the denudation and accumulation geomorphology of Zhongshan structure and the distribution of stratigraphic lithology is diverse. The fault structure is developed. In this geological background, a large number of geological hazards have been induced due to human engineering activities. After a continuous heavy rainfall in middle of September 2009, the roadbed and the shoulder retaining wall were obviously deformed. Although the reinforcement was carried out at that time, it was more than a year later. The deformation of the landslide is increasing, and the degree of damage is becoming more and more serious. The purpose of this paper is to investigate the engineering geological conditions of landslide body and the time and space distribution characteristics of deformation and failure. To analyze the law and mechanism of landslide deformation and failure, to analyze and evaluate the stability of landslide, and to put forward some measures to control the landslide, which is the formation of instability of gravel slope induced by rainfall. The landslide body is composed of artificial fill of Quaternary system. Medium-dense macadam soil and silty clay in plastic-soft-plastic state. The rear edge of the landslide appears on the surface of the semi-excavated and semi-filled subgrade. The settlement deformation of the rear edge highway and the deformation of the retaining wall outside the highway began on 2009. September. At this time, the highway is still in the process of construction; And the landslide in the highway deformation, after the highway completed and opened to traffic, is still worsening, especially after the rainstorm. According to the degree of landslide deformation will be divided into three areas. The deformation is most obvious in the middle and rear part of the landslide. The deformation monitoring data of the landslide body and the rainfall data of the corresponding time period can be compared and analyzed. Although the deformation of the landslide has the lag effect of some time interval compared with the continuous rainfall, there is no doubt that the deformation of the landslide is triggered by rainfall. In addition, the loose material composition of the landslide. The abundant underground water and highway construction load are the important factors to aggravate the deformation of landslide body. The stability of landslide body under heavy rain and natural condition is evaluated by limit equilibrium method and numerical simulation analysis. The results show that the landslide remains basically stable in natural condition and unstable or unstable in rainstorm. The maximum displacement of the landslide body lies in the middle and rear part of the landslide body. Based on this, the measures of both drainage and support are put forward to control the deformation of the landslide body.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U418.55;P642.22

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