Experimental Study on Bentonite-assisted Microbial Solidification of Sandy Soil
In order to study the effect of bentonite types on MICP,calcium-based and sodium-based benton-ites were selected,and different mass ratios(1％,2％,3％,4％)of bentonite were added and mixed with sandy soil under the condition of 1mol/L of the cementation solution,and the curing tests were conducted by mixing method.The results show that the initial pH value of the bacterial solution with the addition of calcium-based bentonite was lower and the urease activity was higher compared with that of sodium-based bentonite,and the unconfined compressive strength of the cured specimens of calcium-based bentonite was all higher than those of the sodium-based bentonite specimens.Therefore,calcium-based bentonite in the MICP curing process is more advantageous.In order to study the optimal conditions for calcium-based ben-tonite-assisted microbial curing of sandy soil,specimens'preparation and strength test were carried out by changing the calcium bentonite content and the concentration of the cementation solution.The results show that the influence of calcium-based bentonite content on specimens'strength is closely related to the con-centration of the cementation solution.When the concentration of the cementation solution is low,the strength of the specimens increases with the increase of calcium-based bentonite content.When the concen-tration of the cementation solution is high,the strength of the specimens increases first and then decrease with the increase of the content of calcium-based bentonite.The optimal conditions for calcium-based ben-tonite assisted microbial solidification of sandy soil within the research range are 2mol/L cementation solu-tion concentration and 2％bentonite content.
bentonitemicrobial curingsandy soilunconfined compressive strengthscanning electron microscope
万方数据
维普
