Constitutive Model of Saturated Soft Clay with Cyclic Loads under Unconsolidated Undrained Condition  

作　　者：李书兆 王建华 

机构地区：[1]State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University [2]Geotechnique Engineering Institute, Tianjin University

出　　处：《Transactions of Tianjin University》2013年第4期260-266,共7页天津大学学报（英文版）

基　　金：Supported by National Natural Science Foundation of China ( No. 51179120)

摘　　要：An equivalent visco-elastic model of saturated soft clay was studied under unconsolidated undrained (UU) condition, which can be used to evaluate the stability of ocean foundation. Cyclic triaxial compression and extension tests were conducted to study the parameters of the model. Results showed that the relationships of the damping ratio and the octahedral shear modulus with the octahedral cyclic shear strain were nearly unique, when the initial octahedral shear stress ratios of specimens were equal to 0.3, 0.5 and 0.7. The relationships of the damping ratio and the octahedral shear modulus with the octahedral cyclic shear strain determined from the cyclic triaxial compression tests were basically the same as those determined from the cyclic triaxial extension tests. Furthermore, the relationships were not related to the initial stress condition, the test stress state and the octahedral cyclic shear stress ratio. The relationships determined from the cyclic triaxial tests under no deviatoric stress were basically the same as those determined from the cyclic triaxial tests under deviatoric stress. The change of the octahedral cyclic accumulative strain with the number of cycles was unique under different tests stress states. An equivalent visco-elastic constitutive model of saturated soft clay under UU condition was initially established.An equivalent visco-elastic model of saturated soft clay was studied under unconsolidated undrained （UU） condition, which can be used to evaluate the stability of ocean foundation. Cyclic triaxial compression and ex- tension tests were conducted to study the parameters of the model. Results showed that the relationships of the damp- ing ratio and the octahedral shear modulus with the octahedral cyclic shear strain were nearly unique, when the initial octahedral shear stress ratios of specimens were equal to 0.3, 0.5 and 0.7. The relationships of the damping ratio and the octahedral shear modulus with the octahedral cyclic shear strain determined from the cyclic triaxial compression tests were basically the same as those determined from the cyclic triaxial extension tests. Furthermore, the relation- ships were not related to the initial stress condition, the test stress state and the octahedral cyclic shear stress ratio. The relationships determined from the cyclic triaxial tests under no deviatoric stress were basically the same as those de- termined from the cyclic triaxial tests under deviatoric stress. The change of the octahedral cyclic accumulative strain with the number of cycles was unique under different tests stress states. An equivalent visco-elastic constitutive model of saturated soft clay under UU condition was initially established.

关 键 词：visco-elastic constitutive model damping ratio octahedral cyclic shear modulus octahedral cyclic shear strain octahedral cyclic accumulative strain cyclic triaxial test 

分 类 号：TU447[建筑科学—岩土工程]