| With the growth of urban population and the development of industrialization,urban solid waste continues to increase.The original landfills can no longer fill the landfill.These early landfills are now located in the city and urgently need to be treated.In recent years,it has been ecologically restored to become a city theme park trend.Repairing it involves multiple geotechnical issues.The composition of garbage soil is extremely complicated,and it has strong spatiotemporal variability.In order to obtain its accurate ultimate bearing capacity and deformation characteristics,it is of great significance for the subsequent large-area filling earthwork for mountain landscaping and safe normal operation.However,it is very difficult to accurately determine its ultimate bearing capacity and deformation characteristics,and large-scale plate load test is a more reliable method.Through the large-scale plate load test with a load plate size of 4m × 4m,the engineering performance of the garbage soil layer in a garbage dump was tested.During the loading process,the plate settlement,the surface settlement around the plate and the layered settlement under the plate,the plate surrounding The deep horizontal displacement is monitored and analyzed during the whole process,and the overall deformation characteristics of the garbage soil layer are obtained.The test results show that the garbage soil layer is deformed by a large amount under load and the influence depth can reach 10 m,which shows the punching and shearing failure mode.The test obtained the characteristic value of the ultimate bearing capacity of the ground layer of the garbage soil layer is 375.0k Pa;the research shows that: under the rectangular load,when the compressive stress reaches 375 k Pa,the settlement deformation of the garbage fill reaches more than 10cm;when the load is low,it appears as shallow soil Subsidence is dominant,and as the load increases,the amount of deep soil settlement gradually increases.On the basis of the field test,combined with the finite element numerical software ABAQUS,a numerical calculation model was established for the large-scale plate load test on the site,and the simulation analysis was carried out.The results of the model calculation showed that the various values were basically consistent with the field load test.Considering that the composition of garbage soil is extremely complex and has strong spatiotemporal variability,the numerical model is used to change the values of the cohesion and internal friction angle of garbage soil,and to study the ultimate bearing capacity of the garbage ground under different working conditions.Changes in force and deformation.As the cohesion and internal friction angle increase,the ultimate bearing capacity of the garbage ground also increases.Whether it is a natural foundation or other special soil load test,there is the problem of size effect of the load plate,and the ultimate bearing capacity and deformation will change as the size of the load plate changes.Numerical analysis The ultimate bearing capacity and deformation of the garbage ground increase with the increase of the size of the load plate.When the load plate edge is up to 5m,the size effect is significantly smaller and tends to remain unchanged. |
