Study On The Stability And Support Structure Of Mawo Slope In The Sichuan Maoergai Hydropower Station

Mawo slope,which is in the Maoergai hydropower station reservoir area,is a rock slope whose excavation height reach to62m.The effect of complicated geological condition have on excavation lies not only the high great depth of load off,but also intense weathering rock on the surface.The slope excavation is controled by the fault zone and exercise strict control over the displacement.The mawo slope have the feature rock slope and soil slope,so the stability and displacement control of the slope is very outstanding,but the most important is the stability of the slope,which decide the safe of hydropower station and the town setting place.therefore,the forecast of excavation and support is a crucial work.In this thesis,the Mawo slope is taken as an example.According to the theory and methods which are from Engineering Geology,Rock Mass Mechanics and Numerical simulation etc.,the author analyes the stability of the slope,and provides some optimizing support-schemeto besure the excavation safe and long time stability.the acquired results are as follows:1、On the basis of surveying the areal geology and the ground geology.the thesis are explicit that the importantest governing factor is the safe of the power transmissing tower and the town.The main research problem of the slope is the stability and displacement afer excavation. And that,the keypoint of this two problem is the fault zone.2、Respectively by transfer coefficient method and numerical simulation, we research the stability of the slope after excavation without supporting structure.and find that if without the supporting structure,not only the stability factor is lesser,and also,the displacement is very large.So it is necessary to support the slope.3、Through the scheme comparison and selection of prevent method of Mawo slope.This paper aim directly at the feature of the slope,and introduced effective measure of " Cable Anchor Frame Beam" to support the slope.Furthermore,the author check the global stability by simple circle sliced method.The conclusion indicate that the stability of the slope improved significantly.4、By simulating the process of excavating and supporting with the Fast Lagrangian Analysis of Continua in Three-dimension(FLAC3D),the author find that the stability and displacement improved markedly.This further proved the supporting structure is reasonable and valid.At last,by changing the cable distribution,The thesis contrast the maximum displacement and optimize the supporting structure.