Laboratory Experiment on Formation of MICP Horizontal Seepage-Reducing Body in Confined Aquifer for Deep Excavation

Using a soil improvement biotechnology based on microbial-induced carbonate precipitation (MICP) to form horizontal water barrier in foundation pit dewatering can not only achieve good control effect, but also the cost and obtain economic environmental benefits. In this study, taking Shanghai layer ⑨ sand as research object, solution injected into by MICP grouting technology includes bacterial (Sporosarcina pasteurii) cementation (urea CaCl2 solution). The migration mechanism of groundwater was analyzed through batch experiment column test, mathematical model established. dynamic adsorption characteristics S. pasteurii, Ca2+, urea were obtained test. Through isothermal Freundlich isotherm used describe pasteurii onto fine sand, partition coefficient found be 1.5 × 10−7 L/mg. Langmuir truly reflect Ca2+ sand. distribution 7 10−8 maximum capacity solute 2404.8 mg/kg. very small. According vertical dispersion 11.5 cm. Due obvious size effect dispersion, sensitivity actual working conditions should subsequent numerical simulation. determined transport parameters provide support for further study simulation process HSRB formed basis field application.