Analysis of 1-D Consolidation of Double-Layered Saturated Porous-Fissured Clay Foundation

doi:10.16183/j.cnki.jsjtu.2021.019

Abstract

Abstract:

In order to study the one-dimensional (1-D) consolidation behavior of double-layered saturated porous-fissured clay foundation, the governing consolidation equations of saturated porous-fissured media were developed based on the mixture theory under the condition of one-dimensional complete confinement. The finite element program for 1-D consolidation of saturated porous-fissured clay was compiled by Fortran language, and the results of single-layered foundation research were used to verify the correctness of this model and program. The influences of compression modulus, permeability coefficient, and soil thickness on the consolidation behavior of double-layered saturated porous-fissured clay foundation were analyzed by using the finite element program. The results show that the consolidation rate of the foundation can be significantly accelerated by increasing the compression modulus and permeability coefficient of the softer topsoil, and the dissipation laws of excess pore water pressure and excess fissure water pressure were different. The dissipation of excess pore water pressure at the base of the foundation would lag behind that of excess fissure water pressure, and the lag would increase with the increase of the permeability coefficient of topsoil. For double-layered saturated porous-fissured clay foundation, improving the softer porous-fissured clay properties of the upper layer can better improve the consolidation behavior of the foundation.

Key words: double-layered foundation, one-dimensional (1-D) consolidation, saturated porous-fissured clay, mixture theory

CLC Number:

TU43

HU Yayuan, WANG Aqiang. Analysis of 1-D Consolidation of Double-Layered Saturated Porous-Fissured Clay Foundation[J]. Journal of Shanghai Jiao Tong University, 2022, 56(4): 443-453.

Figures/Tables 11

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Tab.1

Calculation parameters of model of saturated porous-fissured clay double-layered foundation[3, 15, 20]

土层	E_s/MPa	E_r/MPa	k_F_z×10⁶/(m·s^-1)	k_P_z×10¹⁰/(m·s^-1)	φ^F	φ^P	γ_w/(kN·m^-3)	$α -$ /m^-2
上土层	1.5	2.5	2.47	6.18	0.05	0.4	10.0	10.0
下土层	5.0	8.33	2.47	6.18	0.05	0.4	10.0	10.0

Tab.1

Tab.2

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Tab.3

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