Experimental Study On Mechanical Properties Of Rubber Sand Mixed Soil

With the promotion of national "One Belt And One Road" policy,a large number of highway and railway projects have been built in xinjiang,Inner Mongolia and other desert areas.This region is mostly distributed with loose sandy soil with low shear strength and poor deformation resistance,so it is necessary to find ways to improve the mechanical properties of sandy soil.With the rapid development of automobile industry,people began to pay attention to the disposal of waste tires.Some experts and scholars proposed to mix waste tire particles with sand to form a new composite material(rubber sand mixed soil).Rubber sand mixed soil has the characteristics of light weight,strong resistance to deformation,good permeability and low cost,etc.,which can be used in backfill soil of highway and railway roadbed,slope,retaining wall,etc.,which not only saves energy and environmental protection,but also improves the mechanical properties of sand soil,and has a broad application prospect.However,the theoretical study of rubber sand mixed soil is not mature,in order to make it can be better applied in engineering practice,it still needs to be further studied.In this paper,three axial consolidation drainage(CD)shear test was carried out on rubber sand mixed soil,and the influences of rubber particle weight ratio,rubber particle size,sand particle size and confining pressure on the shear strength characteristics and deviation-stress-axial strain characteristics of rubber sand were studied.The main research contents are as follows:(1)through the triaxial CD test,the influences of rubber particle weight ratio,rubber particle size and sand particle size on the shear strength characteristics of rubber sand mixed soil were analyzed It was found that when the rubber particle weight ratio was 10%,the shear strength of rubber sand mixed soil was the largest.The shear strength of rubber sand decreases with the increase of sand particle size,and is almost unaffected by the rubber particle size.The shear strength of sand mixed with 1-3mm rubber particles is better than that of sand mixed with 2-4mm rubber particles.(2)through the three-axis CD test,the influences of rubber particle weight ratio,rubber particle size,sand particle size and confining pressure on the stress-axial strain characteristics of rubber sand were analyzed.It was found that the peak strength deformation of rubber sand mixed soil increased with the increase of rubber particle content.Under the same confining pressure,the peak strength deformation of the mixed soil also increased with the increase of the particle size of the sand,and was not affected by the particle size of the rubber.Compared with the influence of the quality ratio of rubber particles,the peak strength deformation characteristics of rubber sand are more affected by the grain size of sand.When the mass ratio of rubber sand is 20%-40%,the shear axial deformation of rubber sand mixed soil increases with the increase of confining pressure.