Experimental study on deformation behavior of silty clay under unloading
Experimental study on deformation behavior of silty clay under unloading
复制标题
DOI：
--
复制
发表时间：
2007
影响因子：
1.5
通讯作者：
Yang Xue-qiang
中科院分区：
文献类型：
--
作者：
Yang Xue-qiang
依托武汉长江隧道江北明挖段，对原状粉质粘土进行了K0级固结卸载应力路径排水三轴试验，并深入分析了卸载时的变形特征。分析表明，应力应变曲线与应力路径具有密切的关系，卸载时的应力应变曲线为 类似于双曲型。根据应力应变曲线，卸载应力路径可分为A组和B组。A组应力路径表现为轴压，B组应力路径表现为轴拉。对于原状粉质粘土，其应力应变关系在卸载应力路径下归一化得很好。同一应力路径下不同围压的应力-应变曲线可以用平均围压归一化 但A组和B组的归一化方程不同，并且给出了所有应力路径的归一化方程。该成果可用于进一步研究卸荷作用下土体的变形参数和本构方程。
Relying on the open excavation section of Jiang Bei of the Yangtze River tunnel in Wuhan,a series of drained triaxial tests on unloading stress paths at K0 consolidation have been carried out with undisturbed silty clay.And the deformation characters under unloading were deeply analyzed.Analysis shows that stress-strain curves and stress paths have close relationship and the stress-strain curves under unloading are similar to a hyperbolic type.According to the stress-strain curves,unloading stress paths can be divided into two groups A and B.The stress paths of group A exhibit axial compression and ones of group B show axial tension.The normalization of its stress-strain relationship is very good under unloading stress paths for undisturbed silty clay.The stress-strain curves of different confining pressures in the same stress path can be normalized with average confining pressures.But normalized equations of groups A and B are different.Additionally the normalized equations of all stress paths have been given.This outcome can be used to further research on both deformation parameters and constitutive equation of soils under unloading.