论文标题
增强经过MICP处理的沙质土壤的强度：从微观到宏观秤
Enhancing strength of MICP-treated sandy soils: from micro to macro scale
论文作者
论文摘要
已经对微生物诱导的碳酸钙（CACO3）沉淀（MICP）进行了广泛的研究，以改善岩土工程的土壤。碳酸钙晶体（例如尺寸和数量）的特性会影响MICP处理的土壤的强度。这项研究表明，如何使用微型微流体实验的数据来检查注射间隔的影响以及胶结溶液的浓度对碳酸钙晶体的性质的浓度，以优化宏观尺度砂土土壤柱实验的MICP处理，以提高有效的强度。微尺度实验表明，由于Ostwald成熟，较长的注入间隔使较小的晶体可以溶解并重新沉淀成较大的晶体，而不管胶结溶液的浓度如何。通过在宏观尺度实验中应用这一发现，治疗持续时间为6天，其中注射间隔为12 h，24 h和48 h，用于胶结溶液的浓度分别为0.25 m，0.5 m和1.0 m，足以沉淀出足够大的晶体，以增强有效的强度。这表明，当治疗持续时间从3天增加到6天时，产生了更高的土壤强度和较大的晶体，而当它从6天增加到12天时。
Microbial-Induced Calcium carbonate (CaCO3) Precipitation (MICP) has been extensively studied for soil improvement in geotechnical engineering. The properties of calcium carbonate crystals such as size and quantity affect the strength of MICP-treated soil. This study demonstrates how the data from micro-scale microfluidic experiments that examine the effects of injection intervals and concentration of cementation solution on the properties of calcium carbonate crystals can be used to optimise the MICP treatment of macro-scale sand soil column experiments for effective strength enhancement. The micro-scale experiments reveal that, due to Ostwald ripening, longer injection intervals allow smaller crystals to dissolve and reprecipitate into larger crystals regardless of the concentration of cementation solution. By applying this finding in the macro-scale experiments, a treatment duration of 6 days, where injection intervals were 12 h, 24 h, and 48 h for cementation solution concentration of 0.25 M, 0.5 M and 1.0 M, respectively, was long enough to precipitate crystals large enough for effective strength enhancement. This was indicated by the fact that significantly higher soil strength and larger crystals were produced when treatment duration increased from 3 days to 6 days, but not when it increased from 6 days to 12 days.
