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| BEHAVIOR OF PORE WATER PRESSURE IN DYNAMIC TRIAXIAL TESTS OF SATURATED SOFT CLAY AND ITS EFFECT ON EFFECTIVE STRESS PATH |
| WANG Jun1,GU Chuan1,2,CAI Yuanqiang1,2,YANG Fang1 |
| (1. College of Architecture and Civil Engineering,Wenzhou University,Wenzhou,Zhejiang 325035,China;2. Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education,Zhejiang University,Hangzhou,Zhejiang 310027,China) |
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Abstract The dynamic triaxial test with cyclic confining pressure can apply cyclic confining pressure in addition to the cyclic deviatoric stress,and it can simulate the coupling of cyclic shear stress and cyclic normal stress in earthquakes. The influence of the coupling of cyclic deviatoric stress and cyclic confining pressure on the development of pore water pressure is studied using an advanced global digital systems(GDS) dynamic triaxial device. Test results show that:in pure cyclic confining pressure tests,the cyclic confining pressure can develop the corresponding positive pore water pressure,but cannot develop the corresponding negative pore water pressure;the coupling of cyclic confining pressure and cyclic deviatoric stress makes great influence on the behavior of pore water pressures,the amplitudes of pore water pressures increase greatly in comparison with the conventional dynamic triaxial tests;and the developments of maximum and minimum pore water pressure show different behaviors;and the maximum dynamic pore water pressure continues to grow,while the minimum dynamic pore water pressure stabilizes after a certain number of weeks under loading. Moreover,the residual pore water pressure is defined and the influence of the coupling of cyclic deviatoric stress and cyclic confining pressure on the behavior of effective stress paths is studied.
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Received: 30 December 2011
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