Influence of Rubber Gravel Grade on the Cyclic Shear Properties of the Reinforced-Soil Interface
Rubber gravel,used as base fill,exhibits low shear stiffness and a high damping ratio.To investigate the cyclic shear characteristics of geogrid-rubber gravel,a series of direct shear tests were conducted using a laboratory dynamic direct shear apparatus.The shear stress-shear displacement rela-tionship and volumetric characteristics of the geogrid-rubber gravel interface were performed under four different rubber gravel particle grades(poorly graded GR1 and GR4,well graded GR2 and GR3),three rubber ratios(10%,30%and 60%)and three vertical stresses(30 kPa,60 kPa and 90 kPa).Re-sults revealed that all rubber gravel grades exhibited shear hardening during cyclic shear,but their shear strength decreased to varying degrees compared to pure gravel.Additionally,the shear strength of the rubber gravel increased with increasing vertical stress.Among the four grades,GR2 showed the highest shear strength,though it was still approximately 9%lower than that of pure gravel.The maxi-mum vertical displacement at the interface was positively correlated with both vertical stress and the rubber content,while the continuously graded soils GR2 and GR3 exhibited smaller vertical displace-ments.Under the same particle grade,higher shear frequency and displacement amplitude led to great-er peak shear stress at the mixed soil interface.Furthermore,while the shear stiffness of the reinforce-ment-soil interface increased with the number of cycles,it decreased as rubber content increased.In contrast,the damping ratio exhibited an inverse relationship with shear stiffness.
reinforcement-soil interfacehorizontal cyclic loadingrubber gravelparticle gradation characteristicsdamping ratio
万方数据
维普
