Experimental study on solidification of soft clay based on MICP
CAI Hong, XIAO Jian-zhang, WANG Zi-wen, LI Jie
State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
Abstract：At present, the microbial-induced calcium carbonate (MICP) solidification technology is mainly used in porous sand which is easy to be grouted and connected, but rarely used in low-permeability silt. Based on the results of MICP solidification of sandy soil, using Sporosarcina pasteurii to solidify soft clay, the shear strength index increases obviously with the increase of curing time, the water content decreases greatly during the solidification process and the mechanical properties are improved obviously after solidification, which shows that it is feasible and effective to solidify soft clay by using the MICP technology. In order to understand the solidification mechanism of Sporosarcina pasteurii on the soft clay, the change rules of mineral composition before and after solidification are compared by means of XRD and SEM, and the chemical reaction relationship between Sporosarcina pasteurii and nutrient salts, mineral ions in the soft clay during solidification was determined, and revealed the strengthening mechanism of microbial solidification.
蔡红, 肖建章, 王子文, 李洁. 基于MICP技术的淤泥质土固化试验研究[J]. 岩土工程学报, 2020, 42(S1): 249-253.
CAI Hong, XIAO Jian-zhang, WANG Zi-wen, LI Jie. Experimental study on solidification of soft clay based on MICP. Chinese J. Geot. Eng., 2020, 42(S1): 249-253.
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