【摘要】 将福建标准砂、杭州黄砂和人工石英砂制备成6个砂样,每个砂样只由一种粒径的砂颗粒组成,从每个砂样中选取一定数量的颗粒进行电镜扫描并分析砂样的颗粒平均粗糙度,用弯曲元测试仪测试各砂样在不同孔隙比下的剪切波速(Vs)。对比分析说明颗粒粗糙度对Vs的影响显著,Vs随着颗粒粗糙度的增大而减小。引入粗糙度修正系数,在散粒体介质细观组构与本构关系、弹性粗糙颗粒接触等研究的基础上推导了砂土Vs计算公式。将计算结果与试验实测值进行对比,得到了浅层砂土的粗糙度修正系数的计算方法,讨论了粗糙度修正系数随应力大小的变化趋势。更多还原

【Abstract】 6 sand samples are made by use of Fujian standard sand,Hangzhou sand and man-made quartz sand,respectively,with each sample composed of the single sand particle in diameter.The average particle roughness of every sample and the shear wave velocities(Vs) of each sample in different porosities are obtained by electron microscope and bender element testing equipment.The analytic results indicate that Vs is greatly influenced by the particle roughness,and the magnitude of Vs decreases with the increase of the particle roughness.The roughness coefficient is introduced to deduce the formula of Vs by means of the researches on micro fabrics and constitutive relations of granular materials,elastic contact of rough particles,etc.Moreover,the results drawn from the present method are compared with the measured data,and the calculating method of the roughness coefficient for low sands is obtained.In addition,the relationship between the roughness coefficient and the stress is discussed.更多还原