橡胶-砂混合隔振材料初始变形模量试验研究

Undrained tests on the initial deformation modulus of a rubber particle-sand mixture isolation material

通过对橡胶-砂混合隔振材料开展不排水三轴试验,探究了橡胶含量XC、粒径比d_(50,r)/d_(50,s)、相对密实度D_(r)以及围压σ_(3)对混合料初始变形模量的影响。结果表明:橡胶-砂混合料初始变形模量随着XC的增加呈指数下降,d_(50,r)/d_(50,s)越小,橡胶颗粒对初始变形模量的衰减影响越明显;初始变形模量随D_(r)和σ_(3)的增大而增大,D_(r)越大初始变形模量的增长速度越缓。对初始变形模量按Janbu经验公式进行拟合发现,参数K随橡胶含量的增加而减小;参数n在橡胶含量较小时波动较小,超过30%后离散性增大。最终提出橡胶-砂混合隔振材料初始变形模量归一化预测公式。

A series of consolidated undrained tests were conducted to explore the influences of the rubber content XC,particle size ratio of rubber to sand d_(50,r)/d_(50,s),relative density D_(r) and confining pressureσ_(3) on the initial deformation modulus of a rubber particle-sand mixture.The test results show that the initial deformation modulus of the rubber-sand mixture decreases exponentially with the increase of XC.The smaller d_(50,r)/d_(50,s),the more obvious effect of the addition of rubber particles on the decline of the initial deformation modulus.The initial deformation modulus increases with the increase of D_(r) and σ_(3).The larger D_(r),the slower growth rate of the initial deformation modulus.Fitting the initial deformation modulus according to Janbu’s empirical formula,it is found that the parameter K decreases with the increase of rubber content.The parameter n fluctuates less when the rubber content is small,and its dispersion increases when the rubber content exceeds 30%.Finally,a normalized prediction formula for the initial deformation modulus of the rubber-sand mixture was proposed.