Study On The Performance Of Reinforcement Soil Interface Between Construction Waste And Geosynthetics

With the continuous social development and the increasing of the population.The automobile industry,transportation industry and construction industry are also constantly advancing and consuming a large amount of natural resources,which is accompanied by the generation of numerous construction waste.Meanwhile it has brought many problems,such as occupying land,polluting the environment,etc.,and the treatment for this kind of solid waste needs to consume a lot of manpower and material resources,how to reduce this kind of harm has become an issue that can not be ignored in social development.In this paper,monotone direct shear test,large cyclic shear test,post-cyclic shear test and numerical simulation are carried out,then the experimental results are compared with the numerical simulation results.Specific research results are as follows:The mechanical properties of construction waste mixed soil were measured by direct shear test and screening test.The results show that the optimum moisture content of the mixed soil is about 9.5%,and the maximum dry density is about 1.92g/m~3.There are more large particles in construction waste but less fine particles.The addition of sand increases the proportion for fine particles in soil samples and improves the grading of construction waste soil.Construction waste soil has obvious shear softening in monotone direct shear test and monotone direct shear test after cyclic shear,also the interfacial shear strength and residual strength of soil samples after cyclic shear are greater than the results of monotone direct shear test under the same normal stress condition.In monotonic direct shear test,the soil samples dilated first and then contracted,while in monotonic direct shear test after cycle,the soil dilated obviously.During the cyclic shear process,the soil samples will shear hardening to different degrees in both directions,and the maximum shear stress will increase with the enlargement of normal stress and shear amplitude.The whole soil will shrink with the shear process to a certain extent.After recycling,the shear strength,cohesion and friction angle of the reinforced soil samples have built up obviously.The monotone direct shear test,cyclic shear test and post-cyclic shear test of construction waste soil were simulated by using PLAIXS software.No shear hardening occurs in the simulated curve,and the curve develops gently after reaching the peak point.The residual shear stress is larger than the actual curve,but the peak shear stress at the inflection point is smaller than the actual result.The larger the normal stress is,the closer the peak point of the simulated curve is to that of the actual curve.The whole soil sample presents obvious dilatancy,and the shear required to reach the inflection point of the curve under the same shear path condition is smaller than that required by the actual results.