掺入轮胎橡胶颗粒对砂土剪切性状的影响

Abstract

To enhance the shear strength and reduce the unit weight of sandy fill materials, disposed scrap tire bead was added to sand. The tire bead presented relatively high friction and low unit weight, which led to the formation of reinforced low density mixtures. Direct shear and triaxial compression tests were conducted to observe the effects of scrap tire bead additions and confinements on the shear behaviour of the sand. Stress-strain relations were observed and simulated. It was found that peak shear strength decreased along with increased bead addition, whereas confinements enhanced the peak shear strengths of materials. Peak deviators or peak stress ratios were influenced by bead additions more clearly under high confinements than under low confinements. Poisson’s ratios were associated with the bead additions and the principal stresses. Tire bead additions of 10-20% enhanced sand shear strength under confinements equal to or less than 200 kPa. The stress-strain relationship of the mixtures can be modelled by using Duncan-Chang elastic nonlinear constitutive law.