Variation of hydraulic gradient in nonlinear finite strain consolidation
来源期刊：中南大学学报(英文版)2014年第12期
论文作者：谢新宇 HUANG Jie-qing(黄杰卿) WANG Wen-jun(王文军) 李金柱
文章页码：4698 - 4706
Key words：hydraulic gradient; nonlinearity; finite strain consolidation
Abstract: In the research field of ground water, hydraulic gradient is studied for decades. In the consolidation field, hydraulic gradient is yet to be investigated as an important hydraulic variable. So, the variation of hydraulic gradient in nonlinear finite strain consolidation was focused on in this work. Based on lab tests, the nonlinear compressibility and nonlinear permeability of Ningbo soft clay were obtained. Then, a strongly nonlinear governing equation was derived and it was solved with the finite element method. Afterwards, the numerical analysis was performed and it was verified with the existing experiment for Hong Kong marine clay. It can be found that the variation of hydraulic gradient is closely related to the magnitude of external load and the depth in soils. It is interesting that the absolute value of hydraulic gradient (AVHG) increases rapidly first and then decreases gradually after reaching the maximum at different depths of soils. Furthermore, the changing curves of AVHG can be roughly divided into five phases. This five-phase model can be employed to study the migration of pore water during consolidation.
XIE Xin-yu(谢新宇)1, 2, 3, HUANG Jie-qing(黄杰卿)1, 2, 3, WANG Wen-jun(王文军)2, LI Jin-zhu(李金柱)2
(1. Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China;
2. School of Civil Engineering & Architecture, Ningbo Institute of Technology, Zhejiang University,
Ningbo 315100, China;
3. Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education (Zhejiang University),
Hangzhou 310058, China)
Abstract:In the research field of ground water, hydraulic gradient is studied for decades. In the consolidation field, hydraulic gradient is yet to be investigated as an important hydraulic variable. So, the variation of hydraulic gradient in nonlinear finite strain consolidation was focused on in this work. Based on lab tests, the nonlinear compressibility and nonlinear permeability of Ningbo soft clay were obtained. Then, a strongly nonlinear governing equation was derived and it was solved with the finite element method. Afterwards, the numerical analysis was performed and it was verified with the existing experiment for Hong Kong marine clay. It can be found that the variation of hydraulic gradient is closely related to the magnitude of external load and the depth in soils. It is interesting that the absolute value of hydraulic gradient (AVHG) increases rapidly first and then decreases gradually after reaching the maximum at different depths of soils. Furthermore, the changing curves of AVHG can be roughly divided into five phases. This five-phase model can be employed to study the migration of pore water during consolidation.
Key words:hydraulic gradient; nonlinearity; finite strain consolidation
