Study On Mechanical Properties And Engineering Application Of Scrap Tyre-Soil

With the rapid increasing of the number of cars,a large number of scrap tires will be produced every year,causing serious "black pollution".How to deal with and effectively use these waste tires has become a hot issue in the world.Among them,the direct use of waste tires makes full use of the "stirrup" effect of tires.By filling different types of fillers in the waste tires to improve their mechanical properties and applying to retaining walls,foundation reinforcement,slope protection and other projects,the technology has been successful in countries such as the United States,Canada,France and other countries.However,because of the relative lag of the theoretical research,there are few basic theoretical research achievements on the basic mechanical properties and design calculation methods of the waste tire composite materials,which makes the engineering design undependent and difficult to be popularized and applied in large projects.Therefore,in order to realize the conservation and utilization of resources and give full play to the mechanical efficiency of waste tires,it is necessary to conduct relevant studies on their basic mechanical properties and engineering application parameters.Based on this,this article to scrap tire and soil composite structure unit as the research object,first by full scale compression test,studies the compression properties of complex,puts forward the determination method of complex compression index;Through the direct shear test,the shear characteristics of the interface of the complex were studied,and the shear strength of the complex was calculated.A numerical calculation model was established,and the mechanical analysis of the tyre-soil composite used as retaining wall was carried out,and the horizontal load transfer law was revealed.The main conclusions are as follows:(1)The tensile strength of the waste tyre strip was studied,and the significant"stirrup" effect of the tire was revealed,which could play a certain lateral restriction to the soil.(2)Considering the change of the ratio of the inner and outer diameter of the tire,the compression performance test of the waste tire and soil complex was carried out.The transformation relationship between the deformation modulus of the complex and the deformation modulus of the internal packing was established,and the exponential attenuation of the deformation modulus of the complex with the ratio of the inner and outer diameters of the tire was proposed.(3)Considering the change of the "area ratio" of the waste tires(the ratio of the filler to the cross section area),the waste tire-soil composite scale direct shear test was carried out,and the conversion formula of the shear strength index of the complex and the shear strength index of the filler was put forward.(4)The numerical simulation model was built based on the above test database to investigate the bearing characteristic of tyre-soil retaining wall.through the orthogonal experiment analysis,it is concluded that the internal shear stress main controlling factors of waste tires is verified-soil complex for the feasibility of retaining wall structure.