Ganzi, A Middle School Crag Development Characteristics And Stability Analysis

In the study area is located in ganzi prefectures in sichuan province danba, every year during the rainy season has small dangerous rock collapse, large-scale collapse happened in2009, caused partly damaged below the school walls. Large-scale collapse once it happen again in the study area, threatening objects more than1500teachers and students is the school the entire campus life safety and public facilities, huge potential economic loss, so as to ensure the safety of the middle school and all the teachers and students of life and property, as soon as possible for project management of the study area is necessary. This paper made the following several aspects:1、Based on detailed field geological survey in the study area to collect a large amount of geological data, and with the aid of topographic surveying, engineering geological surveying and mapping, trenching and test a variety of survey methods to find out the distribution of the eight major dangerous rock mass in the study area, morphological characteristics, forming conditions, current situation and development trend.2、According to the dangerous rock mass failure mode is different, can put the dangerous rock instability mode in the study area is divided into dumping, slipping and falling type three types. W2in the study area, the project.it is dumping type dangerous rock, W3, W4, W5, W7belongs to slip type dangerous rock, W1, W6is falling type dangerous rock, you can see the slip type dangerous rock in the area proportion reached50%.3、Based on landform, stratum lithology, geological structure in the study area and rainfall has carried on the analysis and research, has been clear about the formation of dangerous rock is the main cause of topography in the study area and its unique structure and atmospheric precipitation.4、In this paper, using different methods to analyze the stability of dangerous rock in the study area. First qualitative plane projection method is used to judge the stability of dangerous rock, and then using the limit equilibrium method and finite element simulation of the quantitative calculation and evaluation about the present situation of the stability of dangerous rock, finally obtained the following results:under the natural condition of Wl, W4, W6three dangerous rock mass in the unstable state, W5, W7, project.it three dangerous rock mass in the stable state, the other two dangerous rock mass in a stable state; Heavy rain or continuous rainfall conditions, Wl, W4, W5, W6, project.it five dangerous rock mass in the unstable state, the W3, W7two dangerous rock mass in the stable state, W2dangerous rock mass in a stable state; Eight dangerous rock mass under seismic condition all is in not steady state. This result is consistent with practical engineering situation.5、Based on the orthogonal experiment design, the use of the static analytic method, the sensitivity of the influencing factors on the stability of dangerous rock mass are analyzed6、According to the results of stability analysis of dangerous rock is in line with the economic and reasonable, safe and reliable, the engineering application point of view put forward strategies and measures of engineering.