Study On Deformation Response Of Toppling Deformation Rock By Impoundment At Miaowei Hydropower Station On Lancang River

Deformable body formed pouring through a long process of geological history, under natural conditions, stability is generally good. But a large number of engineering cases show Reservoir water can cause deformation of the dumping to continue to develop. Under conditions of water overturned deformation prediction of deformation corresponding dumping rock mass stability analysis is the premise. In this paper, the Lancang River Hydropower three Miao tail Ishikawa left bank slope for example, the combination of field investigations and laboratory tests to analyze the slope stability and deformation after water corresponding. On this basis, the establishment of a dump slope conceptual model to study the deformable body dumped in the water conditions may be deformed discrete element modeling method. The main achievements include:(1) the end of the Lancang River Hydropower three seedlings Ishikawa left bank valley slope which is open asymmetric "V" type valley. Natural slope of about 30 °. Inner slope exposed slate, phyllitic slate and phyllite, slate quartz sand, rock and valley running parallel to the slope of large-scale development overturned deformation.(2) According to the dumping of the degree of deformation of rock dumping, both banks will be strong abutment slope poured into a strong degree of deformation(A), strong(B) and weak dump(C) three types. Geological survey data combined with previous and on-site dumping of rock on the slope of the rock mass structure fine description, analysis of rock slope dump partition features: a strong presence of both left and right abutment slope dumping zone(A zone), strong dumping area( area B), dumping the weak region(C region) rock. A three shihe the left slope area horizontal depth of about 0 ~ 30 m, B horizontal zone depth of about 0 ~ 100 m, C district level depths greater than 100 m.(3) reveal three Ishikawa left bank slope development slate, phyllite, slate full phyllitic should- stress-strain curve obviously similar characteristics; with prolonged water saturated specimen reaches peak intensity a significant increase in the desired strain. Studies have shown that the peak intensity of slate and waterlogged time there is no correlation; phyllite peak intensity over time increasing water saturation significantly reduced. It showed good correlation; phyllitic slate peak intensity over time increasing saturated water tended to decrease, but the correlation was relatively weak phyllite(4) based on discrete element simulation results. The role of water in a long time on the dumping zone phyllite A greater intensity, coupled with the dumping zone A rock is very broken, drastically reduced strength after impounding, compressive strain, deformation of the overlying rock provides a space for the final A zone along the rock lead to dumping dumping dumping zone A and zone B boundary creep slide down wrong. The overall strength of rock dumping area B is stronger than A dumping area, dumping water under the conditions of the deformation zone B zone A relatively small dumping.(5) the dumping of rock-dimensional stability analysis results are based on the limit equilibrium theory suggests that after impounding natural conditions slope stability factor greater than 1.13, in a steady state; in storm conditions, seismic conditions, seismic conditions rainstorm under the stability of 0.946, in an unstable state. Slope in the water level rises during its stability gradually increased, when the water level is stable, due to the gradual infiltration of river slope in vivo, to reduce the physical and mechanical parameters of rock mass, resulting in slope stability decreased gradually; sudden drop in the water level due to move the role of water pressure, slope stability sharp decline, with the hydrodynamic pressure dissipation, stability gradually increased; the water level rise in the process, the rapid increase in slope stability, and finally reaches a steady state.