Study On Mechanical Properties And Discrete Element Method Simulation Of Tire Strip Reinforced Soil

The appearance of automobile has brought great material civilization to human beings,and the number of discarded tires has also increased rapidly.At present,it has become the main “black pollution” in China.The dual nature of environmental pollution potential and resource leads to the need for comprehensive recycling,waste tires need to be treated.Due to the high strength and durability of tires,waste tires are used as derived geotechnical materials and applied to reinforced materials to realize the comprehensive treatment of solid waste and resource recycling.Therefore,the purpose of this paper is to study the basic mechanical properties of waste tire as reinforced material,mainly analyze the mechanical properties and working mechanism of tire reinforced composite,and study its creep properties and development law under the condition of lateral restraint.By using PFC2 D particle flow program,the microscopic phenomenon and mechanism of tire stiffened composite are studied and analyzed from the micro level of particles.The main work and results are as follows:(1)The mechanical properties of silty clay reinforced with tire strips were studied by triaxial compression tests.The stress-strain characteristics of tire reinforced silty clay were normalized,and the normalized equation of stress-strain relationship of tire reinforced silty clay was established.The relationship between shear strength and temperature is negatively correlated at different temperatures.When the confining pressure is 400 k Pa,the shear strength of the specimen with 3% volume reinforcement ratio is 3.16 times that of the specimen without reinforcement.When the volume reinforcement ratio is 3%,the effect coefficient under different confining pressures is2-3 times of that without reinforcement.(2)The effect of concrete particle confinement on the creep behavior of geotechnical materials was studied by creep test in laboratory.The creep characteristic curve and strain load isochron curve of geotechnical materials were analyzed systematically.Through regression analysis of different creep model parameters,three typical empirical creep models were obtained,and the creep development law under different ultimate strength and load level was analyzed.(3)The mechanical properties and working mechanism of incineration slag reinforced with tire strips were studied by direct shear test.The test results show that the strain softening phenomenon appears in the shear stress-strain curve of the sample.The tire strips can increase the friction between the incineration slag particles,limit the relative slip and rotation of the particles,and improve the shear strength.(4)The particle flow simulation was carried out for the incineration slag reinforced by tire,and the stress-strain characteristics and macroscopic-microscopic response of shear were explored.The microscopic mechanical properties were analyzed from the shear deformation,contact force chain,porosity,principal stress deflection and fabric analysis,and the mechanical properties of tire strip reinforced soil were discussed in the field of macroscopic and microscopic.