Analysis Of Seepage Characteristics And The Slope Stability Of High Filled Gravel Soil Slope

With the deepening implementation of the strategy for the development of the western region,the infrastructure construction in the southwest region of China has made considerable progress,and various types of deep excavation and high-fill rock and soil projects have emerged.Due to its high strength and low compressibility,gravel soil is widely used in high fill projects.However,due to the uneven particle size and uneven distribution,under the effect of high groundwater seepage force,the fine particles packed in them can easily be carried away by the groundwater flow and undergo latent corrosion and destruction.Therefore,it is very necessary to accurately grasp the infiltration characteristics and engineering effects of gravel soil.In this paper,an airport high filling project in southwestern mountainous area is taken as an example to study the infiltration characteristics and stability characteristics of high filling gravel soil slope filling materials in the airport through field water injection test and permeability model test,and the numerical simulation is used for the seepage field and stability.Comprehensive analysis of sexual changes and put forward effective prevention and control measures.conclusion as below:(1)By systematically testing the samples in the study area,determine the permeability coefficient,the critical hydraulic gradient range,and the infiltration deformation pattern of the specific filler in the study area,and propose that the original ground slope in the limestone filler area is greater than 13° or the metamorphic sandstone filler.If the original ground slope is greater than 8°,it is the critical point for its infiltration and destruction,and corresponding control measures must be taken.(2)Based on geological surveys and experimental studies,Geo-Studio software was used to simulate the typical profile of the slope,and the process of saturation and stability change of the high-fill slope under seepage was analyzed.The weak location of the high fill slope.Based on the research results,it is recommended that drainage layers and blind ditch be provided at the bottom of the building during the construction phase to reduce the hydraulic gradient,and a slope protection structure such as an inversion layer be provided at the foot of the slope to prevent the occurrence of infiltration deformation.(3)Analysis of slope stability and related conclusions: As the rainfall continues,the safety factor of slope stability continues to decrease;at the end of the rainfall,the safety factor still decreases;but with the infiltration of rainwater,The safety factor will increase slowly.It can be seen that the impact of rainfall on the stability of high-fill slopes has a long-term and obvious hysteresis effect.At the same time,short-term heavy rainfall has a greater impact on slope stability,while sustained medium-intensity rainfall has a greater impact on slope stability.