An Analysis And Evaluation On Stability Of The Northern Slope In Bai Jigou’s End Open Pit Coal Mine

Reserves of Coal resource in our nation are sufficient and are spread throughout our nation, however, the resource of Taixi coal is quite limited. As for Taixi coal, it not only can be used by ordinary people in their daily life and the industry of steel, but also can be utilized in the coal chemical industry, as good as the metallurgy. However, the stability of side slope is of importance if opencast way is employed when mining Taixi coal. The deformation and landslip of side slope in opencast mine happened frequently; therefore, it may let the economic loss, as good as the danger of workers’ life without accurate forecast for the trend of deformation and landslip of side slope. Bai Jigou coal mine now are employing the opencast way, so the final index of north side slope influences the output, meanwhile, the satiability of side slop influences production. This thesis tries to reset the index of the circle of the slope in Bai Jigou coal mine so as to make an analysis on the stability of the side slope, furthermore, to improve the output and the economic benefit on the basis of safety in production. Here is a brief introduction to geological condition of Bai Jigou coal mine: the stratum which contains coal resources are Jurassic Yan’an Formation in the northern part of the mine, the average depth of the stratum is about231.00m and are composed of meat bog, lakes and bed phase. The composition mainly are quartz, parts contain gravel, and most of the gravel are glutenite, which are highly silicified. The coal seam of top and bottom lithology are made up of aleurolite and fine sandstone; the overall hydrogeological feature is that the water supply for each aquifer are insufficient, however, the condition of drain are good. The stability of the final side slope is affected by its own weight. Comprehensively, by using limit equilibrium mathod to compute the index of stability for northern final part of the mine, by using numerical modeling to make a checking calculation of limit equilibrium, and also by analyzing the condition of stress within the slope, the thesis tries to find the zone where landslide are easily happened. The index of stability is accordance with the result of checking calculation when using numerical modeling, therefore, the latent zone of landslide is discovered and some protective measures are suggested accordingly.