摘要
饱和软黏土的小应变剪切模量Gmax是其基本力学参数。在进行饱和软黏土的有效应力动力分析时,往往认为小应变剪切模量Gmax只随着有效应力的降低而衰减,而不受动荷载应力历史的影响,因此基本采用静力状态下得到的小应变剪切模量代替相同有效应力时动力状态下的小应变剪切模量。但是,对于饱和软黏土,目前并没有足够多的试验数据证明这一假设。基于这一考虑,通过GDS动三轴及弯曲元测试系统,研究了循环应力历史对饱和软黏土小应变剪切模量的影响,试验结果表明循环应力历史对Gmax的影响较大,采用静力状态下得到的Gmax代替动力状态下的Gmax并不可取。同时,发现可以使用小应变剪切模量的突变来表征饱和软黏土的结构破坏。
The small-strain shear modulus is the main physical index of saturated clays. In the methods for the effective stress analysis, the mall-strain shear modulus obtained from static tests is often used in the dynamic analysis without regard to the influence of loading history. However, for saturated clays, this assumption has not been proved by enough test data. Based on this consideration, a few cyclic triaxial and bender element tests were conducted to study the influence of loading history on the small-strain shear modulus of saturated clays. The test results indicate that the influence is great and the above assumption is not correct. Meanwhile, it is also found that the small-strain shear modulus can be used to determine the failure criterion of saturated clays under cyclic loading.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2012年第9期1654-1660,共7页
Chinese Journal of Geotechnical Engineering
基金
国家杰出青年基金项目(51025827)
国家自然科学基金项目(50979096
50808145
51109164)
973项目(2011CB411907)
浙江省自然科学基金项目(R1080819
Y1090105
Y1110751)
浙江省科技计划项目(2010C33182)
温州市科技计划项目(S20100030)
关键词
小应变剪切模量
弯曲元
动三轴
应力历史
small-strain shear modulus
bender element
cyclic triaxial test
loading history
