%0 Journal Article
%A LI Zheng-hui
%A WANG Shi-mei
%A GUO Zhen
%A LU Peng
%A JIN Lai-fu
%T Expression of <em>k-n</em> Based on Fluid-solid Coupling Experiment
%D 2017
%R 10.11988/ckyyb.20160479
%J Journal of Yangtze River Scientific Research Institute
%P 106-110
%V 34
%N 8
%X The expression of <em>k-n</em> is crucial in the analysis and calculation of fluid-solid coupling problems in geotechnical engineering. The relationship of <em>k-n</em> obtained from conventional laboratory seepage test deviates from reality as the fluid-solid coupling effect is not considered. To get a more accurate relationship between porosity and permeability coefficient, triaxial fluid-solid coupling test under varying consolidation pressure was conducted on a self-developed SRS-1 seepage and creep coupling test apparatus. The variation of porosity against time was obtained, and the fitted expressions of <em>k-n</em> with and without fluid-solid coupling effect are acquired. The expressions together with Kozeny-Caman's empirical formula were analyzed and then were used in the numerical simulation of one-dimensional saturated foundation consolidation in consideration of fluid-solid coupling. Then the calculation results were compared with the result of classical seepage mechanics method. Results show that 1) fluid-solid coupling effect should be taken into consideration as porosity changes dynamically in the process of seepage; 2) fluid-solid coupling problem should not be solved with classical seepage mechanics method, otherwise the error is too big; 3) since Kozeny-Caman's empirical formula, which is widely used in numerical simulation of fluid-solid coupling problem, could not accurately reflect the relationship between permeability coefficient and porosity of clay, we do not recommend it for numerical modeling; 4) the expression of <em>k-n</em> in consideration of fluid-solid coupling effect is recommended to improve the accuracy of numerical simulation results.
%U http://ckyyb.crsri.cn/EN/10.11988/ckyyb.20160479