不同加载比时砂砾料动模量和阻尼比变化规律研究  

Study on dynamic modulus and damping ratio of sand gravel under different loading ratios

作　　者：王景 WANG Jing(Xinjiang Water Resources and Hydropower Survey Design and Research Institute Co.,Ltd.,Urumqi 830000,China)

机构地区：[1]新疆水利水电勘测设计研究院有限责任公司,新疆乌鲁木齐830000

出　　处：《水利水运工程学报》2023年第1期95-103,共9页Hydro-Science and Engineering

摘　　要：为探究加载比和围压对砂砾料动力特性的影响,通过大型动三轴试验,研究不同加载比和围压作用下砂砾料动模量和阻尼比的变化规律。研究结果表明:(1)随着加载比的增大,动应变显著增大,孔压明显上升,最大阻尼比增大;(2)试验数据更能反映出阻尼比随动剪应变发展的变化规律,综合考虑各动力参数的变化,建议砂砾料动模量和阻尼比试验的加载比选择范围为1.5~2.0;(3)采用分段拟合法对动应变小于0.01%和大于0.01%的试验数据进行拟合,直线与试验点的拟合度均大于0.96,分段拟合不同试验条件下砂砾料本构关系更为合理;(4)不同试验条件下动剪切模量比与参考剪应变具有良好的归一性,通过二元线性回归得到砂砾料最大动剪切模量关于围压和加载比的经验公式。该方法可为砂砾料动三轴试验及数据处理提供参考。In order to explore the dynamic characteristics of sand gravel under the action of loading ratio,through largescale dynamic triaxial tests,the change laws of dynamic modulus and damping ratio of sand gravel under different loading ratios and confining pressures is studied,and the influence of different loading ratios and confining pressures on the dynamic parameters of sand gravel was analyzed.The results show that:(1)With the increase of loading ratio,the dynamic strain increases significantly,the pore pressure increases significantly,and the maximum damping ratio increases;(2)The test data can better reflect the variation law of damping ratio with the development of dynamic shear strain.Considering the changes of various dynamic parameters,it is suggested that the selection range of loading ratio of dynamic modulus and damping ratio test of gravel should be 1.5-2.0;(3)The test data with dynamic strain less than 0.01%and dynamic strain greater than 0.01%are fitted by the subsection fitting method.The fitting degree between the straight line and the test point is greater than 0.96,and the subsection fitting is more reasonable under different test conditions;(4)Under different test conditions,the dynamic shear modulus ratio and the reference shear strain have good normalization,and the test data are reliable.Through binary linear regression,the empirical formula of the maximum dynamic shear modulus of gravel about confining pressure and loading ratio is obtained.This method can provide a reference for dynamic triaxial test and data processing of gravel materials.

关 键 词：砂砾料 动模量 阻尼比 加载比 最大动剪切模量 

分 类 号：TV641[水利工程—水利水电工程]