Consolidation behaviors of soft marine clay in Lianyungang under desalination environment of pore water
DENG Yong-feng1, 2, YUE Xi-bing1, 2, ZHANG Tong-wei1, 2, LIU Song-yu1, 2, YANG Zhong-chao3
1. Institute of Geotechnical Engineering, Transportation College, Southeast University, Nanjing 210096, China; 2. Key Laboratory of Urban Underground Engineering and Environmental Safety of Jiangsu Province, Nanjing 210096, China; 3. Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education, Chongqing Jiaotong University, Chongqing 400074, China
Abstract：The marine soft clays, the quaternary sediments, are widely deposited in the sea transgression/regression environment in Lianyungang, Jiangsu Province, whose behaviors are focused recently with the implementation of the coastal development strategy. The salinity of pore water during deposition is relatively high, and with the erosion of the surface or underground freshwater, the desalination of pore water occurs, whilst its effect on soil behaviors of the natural soft clays is still unclear. The piezo-cone penetration tests (CPTu) and physical property experiments of the soft clays with salinity of pore water of 0.1% and 4.9% at two sites, e.g. Lianyungang-Linyi highway and Linhai highway, are conducted. The higher strength of the soils with more salinity at the same depth is observed, but they have the similar deposition environment, ratios of water content to liquid limit, particle-size distributions and mineral compositions. To further clarify the effect of pore water, the paralleled percolation and oedometer tests with the synthetic solution and deionized water are performed. The results show that the parameters of oedometer modulus EOed, consolidation coefficient Cv and hydraulic conductivity k with the synthetic solution are higher than those with deionized water, while the compression index Cc, swelling index Cs and secondary consolidation coefficient Cα are on the contrary. Those results will deepen the understanding of behaviors of Lianyungang marine clays and provide the reference for the offshore engineering.
邓永锋, 岳喜兵, 张彤炜, 刘松玉, 杨忠超. 连云港海相软土在孔隙水盐分溶脱环境下的固结特性[J]. 岩土工程学报, 2015, 37(1): 47-53.
DENG Yong-feng, YUE Xi-bing, ZHANG Tong-wei, LIU Song-yu, YANG Zhong-chao. Consolidation behaviors of soft marine clay in Lianyungang under desalination environment of pore water. Chinese J. Geot. Eng., 2015, 37(1): 47-53.
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