Variable cross-sectional pore model to describe hydraulic conductivity and water retention behaviors of geotechnical materials
ZHANG Zhao1, CHENG Jing xuan1, LIU Feng yin1, QI Ji lin1,2, CHAI Jun rui3, LI Hui yong4
1. Institute of Geotechnical Engineering, Xi'an University of Technology, Xi'an 710048, China; 2. College of Civil and Transportation Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; 3. State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China (Xi'an University of Technology), Xi'an 710048, China; 4. Sinohydro Foundation Engineering Co., Ltd., Tianjin 301700, China
Abstract：To investigate the contribution of their non-uniform cross-section to hydraulic conductivity and water retention behaviours for geotechnical materials, the pores can be simplified as variable cross-sectional assembly of cylindrical macro-pores with pore throats. In addition, this variable cross-sectional pore model can provide theoretical expressions for both the saturated-relative hydraulic conductivity functions and the water retention curves based on a fractal pore size distribution. Finally, these theoretical expressions are validated against both the saturated-unsaturated permeability data for four sandstones and eight soils and the hysteretic water retention data (including the supplementary water retention tests on a clay) for three soils in the previous literatures. The results of RMSD between the predicted and the measured values of saturated permeability and relative hydraulic conductivity show that these new expressions are superior to Kozeny-Carman equation and Assouline model for describing the evolution of saturated permeability with porosity and the relation of relative hydraulic conductivity with effective degree of saturation.
张昭, 程靖轩, 刘奉银, 齐吉琳, 柴军瑞, 李会勇. 基于变截面孔隙模型描述岩土介质的渗透及持水特性[J]. 岩土工程学报, 2020, 42(10): 1807-1816.
ZHANG Zhao, CHENG Jing xuan, LIU Feng yin, QI Ji lin, CHAI Jun rui, LI Hui yong. Variable cross-sectional pore model to describe hydraulic conductivity and water retention behaviors of geotechnical materials. Chinese J. Geot. Eng., 2020, 42(10): 1807-1816.
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