Abstract:Conducted triaxial CD tests on 7 different proportions of dry rubber-sand mixtures under six confining pressures. Studied the effects of proportions and confining pressures on properties of shear strength, deviatoric stress-axial strain curves and volumetric strain-axial strain curves of rubber-sand mixtures. The results indicate that: it is beneficial to improve the shear strength properties of sand when the mass fraction of rubber particles is 0%~30%; the angle of internal friction appears the maximum value near to 10% mass fraction; the cohesion appeared the maximum value near 20%. The characteristics of the deviatoric stress-axial strain curves of the rubber-sand mixtures are similar to that of pure sand when the mass fraction is less than 50%, exhibiting hyperbolic curves, and when the mass fraction is no less than 50%, the mixtures are similar to pure rubber particles, exhibiting linear elastic. The rubber sand model parameters(such as the peak deviator stress, initial tangent modulus and failure ratio) obtained from hyperbolic model fitting increase with confining pressures increment and decrease with rubber content increment. The characteristics of volumetric strain- axial strain curves of the mixtures are similar to pure sand when rubber mass fraction is not over 20%, exhibiting contraction followed by dilatation, and above 20%, it appears the characteristics of monotonic shearing shrinkage, and the rubber particle content is more, the shear shrinkage is more obvious.