坝基含砂黏土的动剪切模量和阻尼比试验研究  

Experimental study on dynamic shear modulus and damping ratio for clay with sand of dam foundation

作　　者：陈智慧[1,2] 余湘娟[1,2] 高磊[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学岩土工程研究所,江苏南京210098

出　　处：《水运工程》2014年第6期146-150,共5页Port & Waterway Engineering

基　　金：河海大学中央高校基本科研业务费专项资金项目(2012B02314);中国博士后科学基金资助项目(2012M511193);江苏省博士后科研资助计划项目(1102073C);高等学校博士学科点专项科研基金(20120094120015)

摘　　要：通过对某大坝坝基的含砂黏土试样开展共振柱试验,得到含砂黏土在10^-6 ～ 10^-4剪应变处的动剪切模量G与阻尼比D的变化曲线及规律,分析了固结压力对动剪切模量、阻尼比和最大动剪切模量的影响,讨论了最大动剪切模量和最大阻尼比随含砾量变化的规律.研究结果表明,在小应变（10^-6～10^-4）范围内含砂黏土动剪切模量G随剪应变γ增大而衰减,随团结压力增大而增大;阻尼比D随剪应变增大而增大;最大动剪切模量Gmax随着含砾量的增加而增大,但最大阻尼比随含砾量的增加而减小.The variation curves and rules of dynamic shear modulus and damping ratio for clay with sand within the shear strain range of 10^-6 up to 10^-4 are obtained by the resonant column test. The influence of the confining pressure on dynamic shear modulus, damping ratio and the maximum dynamic shear modulus is discussed. The variation rules of the maximum dynamic shear modulus and maximum damping ratio with the gravel content are analyzed. The results show that within the small shear strain （ 10^-6 -10^-4）, the dynamic shear modulus G falls as the augmentation of shear strain γ, and rises with the enhancement of the confining pressure; The damping ratio increases along with the accretion of the shear strain y; With the increase of gravel content, the maximum dynamic shear modulus enhances, but the maximum damping ratio decreases. The results may serve as reference for similar projects.

关 键 词：含砂黏土 动剪切模量 阻尼比 共振柱试验 

分 类 号：TU435[建筑科学—岩土工程]