相对密实度对含黏粒砂土动剪切模量与阻尼比影响的试验研究

Experimental Study of the Effect of Relative Compactness on Dynamic Shear Modulus and Damping Ratio of Clayey Sand

摘要:

利用GCTS共振柱系统开展一系列含黏粒砂土的动力特性试验，研究相对密实度对含黏粒砂土动剪切模量和阻尼比的影响，并探讨其影响规律。试验结果表明：相对密实度对动剪切模量、动剪切模量比、阻尼比、最大动剪切模量均有影响。动剪切模量随着相对密实度的增加而变大，但动剪切模量增大的幅度更大；当黏粒含量较小时，动剪切模量比随相对密实度的增加而变大，当黏粒含量较高（≥16%）时，相对密实度对动剪切模量比基本没有影响。阻尼比随相对密实度的增加逐渐变小；最大动剪切模量随相对密实度的增加而增大，但黏粒含量不同，其最大动剪切模量增大幅度不同，同时建立最大动剪切模量随相对密实度变化的关系式，并给出相关参数。

Abstract:

Using GCTS' resonant column system, we conducted a series of dynamic behavior tests of clayey sand to study the effects of relative compactness on the dynamic shear modulus and damping ratio of clayey sand. We also considered the influence law. The test results show the relative compactness to have an effect on the dynamic shear modulus, the dynamic shear modulus ratio, the damping ratio, and the maximum dynamic shear modulus. The dynamic shear modulus was found to increase with increases in the relative compactness. When the clay content is low, the dynamic shear modulus ratio was found to increase with increases in the relative compactness. When the clay content is high (≥16%), however, the dynamic shear modulus ratio was found to be hardly affected by the relative compactness. We found the damping ratio to decrease with increases in the relative compactness. The maximum dynamic shear modulus was found to increase with increases in the relative compactness, but the increase in amplitude differed with different clay contents. We established the relation between the maximum dynamic shear modulus and the relative compactness, and provide the relevant parameters.