利用带弯曲元波速测试的三轴仪对不同密实度下饱和丰浦砂进行了侧向静止土压力系数K0固结试验,旨在得出丰浦砂在不同密实度下K0值,并通过弯曲元波速测试计算K0固结条件下饱和砂的小应变剪切模量。研究表明:随着砂土密实度的增加,K0变小。同时,确定了K0固结下砂土的小应变剪切模量G0随有效围压和密实度的变化,并确定了G0预测公式中的参数A和n的值。基于试验成果,进一步尝试建立了丰浦砂K0系数和其小应变剪切模量G0的关系。
One-dimensional consolidation tests were carried out in a stress path triaxial to investigate the coefficient of lateral earth pressure K0 of saturated Toyoura sand with different densities. Bender elements for shear wave measurement were installed in the triaxial device. The shear wave velocity of sand specimens can be measured under the K0 stress state and then the small strain shear stiffness G0 of Toyoura sand can be calculated. Results demonstrated that the value of K0 decreases as the density of sand increases. Furthermore, the effects of effective mean confining pressure and density on shear modulus G0 at small strain were also investigated. Parameters A and n in the empirical equation for predicting the G0 of sand sample during the K0 stress rate were determined. Moreover, the relationship between K0 and G0 was analyzed and it was found that K0 decreases almost linearly as G0 increases.
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