| With the continuous development of science and technology,the automobile industry is changing with each passing day,and there has been a spurt of growth in waste automobile tires in various countries.The conventional way to deal with scrap tires is incineration,which will not only cause waste of resources,but also cause pollution to the environment,so domestic Foreign scholars proposed to combine sand particles with waste rubber particles to form a new composite material-rubber-sand mixtures.The change of wave load or seismic load sometimes shows a state in which the amplitude of dynamic load does not change,but the dynamic principal stress keeps rotating.The dynamic torsional shear test was carried out with a torsional shear instrument.Considering different consolidation methods,the rubber-sand mixtures with rubber content of 5%,10%,15%and rubber particle size of 1mm,2mm,3mm and 4mm was studied.Liquefaction characteristics,including pore-pressure ratio,axial strain,shear strain,generalized shear strain and the variation law of effective stress,through the hierarchical loading method,the deformation characteristics of rubber-sand mixtures,including stress-strain hysteresis curve,shear The changing law of modulus,damping ratio and dissipated energy,the specific research content and results are as follows:（1）Through two different consolidation methods,the particle size ratio and rubber content of the rubber-sand mixtures were changed to explore the liquefaction characteristics of the mixed soil.The results showed that under the isotropic consolidation method,4mm rubber particles can Increasing the liquefaction cycle of the sample,the sample with a rubber content of 15%liquefies the fastest;in the anisotropic consolidation mode,changing the particle size or content of rubber particles has a greater impact on the development law of the liquefaction cycle and pore pressure ratio.In addition,with the increase of the consolidation ratio,the more rubber content,the greater the pore pressure ratio cycle amplitude of the sample.（2）Through two different consolidation methods,the development law of shear strain,axial strain and generalized shear strain with cycle times was explored.The development trend is slow,and then continues to increase.Under the anisotropic consolidation mode,the development trend shows a rapid growth in the early stage,and then gradually tends to be stable;the development trend of the shear strain of the sample is significantly affected by the consolidation mode.Under the isotropic consolidation mode,the The shear strain increases gradually with the increase of the cycle times.In the anisotropic consolidation mode,the shear strain is the largest when the load is just acting,and gradually decreases with the increase of the cycle times.（3）The influence of the consolidation ratio on the development law of the stress-strain hysteresis curve was explored by changing the rubber content and rubber particle size.The test results show that when the consolidation ratio is 1.0,the hysteresis loop of the sample is the smallest when the rubber content is 15%,when the consolidation ratio is 1.5,the hysteresis circle of the sample is the smallest when the rubber content is 5%,and when the consolidation ratio is 2.0,the size of the hysteresis circle is almost not affected by the rubber content;control the rubber content and rubber particle size Similarly,it is found that when the consolidation ratio is 2.0,the hysteresis cycle of the sample is the smallest;when the rubber particle size increases from 1 mm to 4 mm,the hysteresis cycle of the sample decreases gradually,and is not affected by the consolidation ratio.（4）The effects of rubber content,rubber particle size and consolidation ratio on the development law of the shear modulus and damping ratio of the samples were studied by hierarchical loading.The test results showed that when the consolidation ratio was 1.0,the shear modulus decreased slowly,and the consolidation ratio When it is 1.5 and 2.0,the shear modulus decreases rapidly.The increase of the consolidation ratio from 1.0 to 2.0 can improve the shear modulus and damping ratio of the sample,and the shear modulus of the sample increases with the increase of rubber content.The damping ratio is the smallest when the rubber particle size is 4 mm,and the damping ratio is the largest when the rubber content is 15%.（5）Through the hierarchical loading method,the rubber content and rubber particle size were changed,and the influence of the consolidation ratio on the development law of the dissipated energy of the sample was analyzed.The test results show that under the same double-amplitude shear strain,the dissipative energy varies with the solid The increase of the binding ratio increases;in the isotropic consolidation mode,the dissipative energy is the largest when the rubber content is 15%,and in the anisotropic consolidation mode,the dissipation energy gradually decreases with the increase of the rubber content.Small;no matter what kind of consolidation method,to achieve the same double-amplitude shear strain,large particle rubber needs more energy dissipation. |
