摘要
在小应变水平下土体的刚度特性明显不同于常规试验得到的土体刚度,正确评价土体的小应变特性对于基坑、隧道等地下工程的变形分析具有重要作用。采用装有霍尔效应局部应变传感器的三轴试验和配有弯曲元的共振柱试验,研究上海典型天然黏性土的小应变特性。研究表明,随着土体深度的增加,土体剪切模量增大;第(2)^(5)层的小应变刚度衰减规律基本一致,第(6)层土因其明显的超固结特性,其刚度衰减速率明显大于其他土层;共振柱试验给出了各层土样的初始剪切模量以及归一化剪切模量比与剪应变的关系;三轴和共振柱试验均揭示了上海典型黏性土的剪切模量在小应变范围内随剪应变增加呈非线性衰减的规律。
The stiffness of soils at small strain level is different from that at large strain level obtained by normal triaxial tests. Small-strain characteristics of soil play an important role in the analysis of deformation in deep excavations, tunnels and other underground engineering. A series of static triaxial tests equipped with Hall Effect local strain transducers and dynamic tests using resonant column with bender element are carried out to study the small-strain characteristics of typical Shanghai natural clays（i.e. Layer 2~Layer6）. The results of this study show that the shear modulus increases with the increase of depth of soil layer. Shear modulus of the over-consolidated Layer 6 decays more rapidly than that of the other normally consolidated layers（i.e. Layer 2~ Layer 5）. The initial shear modulus and the normalized shear modulus degradation are obtained by the resonant column. Both the triaxial tests and the dynamic tests can reveal the non-linear decay trend of shear modulus with the increasing of shear strain.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2017年第12期3590-3596,共7页
Rock and Soil Mechanics
基金
上海市浦江人才计划项目(No.15PJ1433500)
"十二五"国家科技支撑计划课题(No.2012BAJ01B02)~~
关键词
上海黏性土
小应变特性
刚度衰减
初始剪切模量
非线性
Shanghai cohesive soils
small-strain characteristic
stiffness decay
initial shear modulus
non-linear
