南通典型土类动剪切模量比和阻尼比的统计分析

Statistical analysis of dynamic shear modulus ratio and damping ratio of typical soils in Nantong

根据南通地区的586组共振柱试验土动力参数数据,采用Davidenkov动本构模型拟合得出7种土类在8个典型应变下的动剪切模量比和阻尼比,结合数理统计确定其分布形态和参考值范围,进而研究不同类型土体的动剪切模量比和阻尼比随剪应变变化非线性关系的不确定性问题。通过平均化处理,给出南通常见土类的推荐值,并与规范值、袁晓铭推荐值进行对比分析。最后分析了埋深对粉砂和粉质黏土动剪切模量比和阻尼比与剪应变关系的影响,总体而言,埋深10~30 m粉砂和埋深90~150 m粉质黏土的动剪切模量比对埋深变化更敏感。

According to the soil dynamic parameter data of 586 groups of resonance column test in Nantong,Davidenkov dynamic constitutive model was used to fit the dynamic shear modulus ratio and damping ratio of 7 types of soil under 8 typical strains,and their distribution forms and reference ranges were determined by mathematical statistics.Then the uncertainty of the nonlinear relationship between dynamic shear modulus ratio and damping ratio of different types of soils with shear strain was studied.By means of averaging,the recommended values of common soil types in Nantong were given and compared with the standard values and Yuan Xiao-ming's recommended values.Finally,the influence of buried depth on dynamic shear modulus ratio,damping ratio and shear strain relationship of silty sand and silty clay was analyzed.In general,the dynamic shear modulus ratio of silty sand at 10-30 m deep and silty clay at 90-150 m deep is more sensitive to the change of buried depth.