| There are many airpors in the southwest or under construction,due to the large number of mountainous areas,terrain and geological conditions are complex,the airport construction with more digging,high filling,high seismic intensity and so on.And the high fill slope instability also to the people's lives and property and economic construction to bring serious losses.Therefore,the study of the mechanism of high-slope slope instability is of great significance to the construction of the project.Based on the 500 g t large-scale geotechnical centrifuge of Chengdu University of Technology and the 12 # landslide of Panzhihua Airport,this paper simulates the deformation and failure characteristics of slopes in the case of rainfall and groundwater.It aims to reproduce the damage process,through high-speed cameras and a series of tests Components,analysis and discussion of its sliding damage mechanism,the main research results are as follows:(1)Designed and developed a new type of centrifugal model rainfall test device,including atomization centrifugal sprinkler system,pressurized pressure system,lighting system,the device can be sealed with the model box,effectively solve the previous centrifuge rainfallproblem.(2)Based on the model,the three-dimensional centrifugal model was built according to the model N = 400,and the distribution of the sand body and mudstone was considered,and the three-row anti-groundwater simulator,as far as possible on the airport to fill the real situation of high fills.In the case of 150 g acceleration,the rainfall simulation is carried out in order to restore the deformation and failure process of the high fill slope.A total of the use of test components earth pressure sensors,pore water pressure sensors,strain gauges,displacement sensors,with the number of more than 60.(3)The experimental results and monitoring components show that the slope in the early settlement to creep-based,the maximum settlement 4cm,equivalent to the prototype 6m.And at the beginning of the deformation,it was assumed that the rows formed a small crack,and after about 2000 s after the rain,the U1 pore water pressure sensor located in the shoulder was the first to react,and the pressure of the infiltration hole was increasing,Up to 84.43 kPa.(4)Deformation stage after two heavy rain,the slope was at significant sliding damage.At this stage,due to continuous creep earth pressure has been reduced,the pile pressure has been increased to 66.22 MPa.Strain data from the pile can also be seen,the back row of the pile by the internal force is far greater than the front row,the pile facing the sliding direction of the internal force than the back large.(5)Experimental model failure begins at the top of the slope platform,the slope shoulder part of the largest deformation,and from the plane to see the left side of the deformation than the right side.The test results are similar to those of the 12 # landslide and deformation process.The landslide sliding mechanism is deepened from the aspects of slope deformation and fracture characteristics,anti-slide pile force,pore pressure and so on.It is proved that the sliding mechanism of the landslide is creep-With overrides. |
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