Rock-like behavior of biocemented sand treated under non-sterile environment and various treatment conditions

作     者：Meghna Sharma Neelima Satyam Krishna RReddy Meghna Sharma;Neelima Satyam;Krishna R.Reddy

作者机构：Discipline of Civil EngineeringIndian Institute of Technology IndoreIndore453552India Department of CivilMaterialsand Environmental EngineeringUniversity of Illinois at ChicagoChicagoILUSA 

出 版 物：《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报（英文版）)

年 卷 期：2021年第13卷第3期

页      面：705-716页

核心收录：

学科分类：081401[工学-岩土工程] 08[工学] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0813[工学-建筑学] 0814[工学-土木工程] 

基　　金：Indian Institute of Technology Indore  IITI 

主　　题：Bacteria Microbially induced calcite precipitation (MICP) Soil stabilization Microstructure Calcite content 

摘      要：Microbially induced calcite precipitation(MICP)is a recently developed technique for microbiological ground improvement that has been applied for mitigating various geotechnical ***,the major challenges,such as calcite precipitation uniformity,presence of different bacteria,cementation solution optimization for cost reduction,and implementation under non-sterile and uncontrolled field environment are still not fully explored and require detailed investigation before field *** study aims to address these challenges of MICP to improve the geotechnical properties of sandy *** series of experiments were conducted using poorly graded Narmada River(India)sand,which were subjected to various biotreatment schemes and tested for unconfined compressive strength(UCS),split tensile strength(STS),ultrasonic pulse velocity(UPV),hydraulic conductivity(after 6 d,12 d,and 18 d of treatment),and calcite *** microstructure of sand was examined through a scanning electron microscope(SEM).Initially,the sand was individually augmented with two non-pathogenic bacterial strains,***(S.)pasteurii and Bacillus(B.)*** stopped-flow injection method was adopted to provide cementation solutions at three different durations(treatment cycle)of 12 h,24 h,and 48 h and three different pore volumes(PVs)of 1,0.75,and *** pore volume here refers to the porosity which is expressed as a ratio,i.e.a porosity of 50%was used as *** results showed rock-like behaviors of biocemented sand with the UCS,STS,and UPV enhancement up to 2333 kPa,437 kPa,and 2670 m/s,*** hydraulic conductivity reduction of 96.6%was achieved by 12%of calcite formation after 18 d of treatment using Sporosarcina pasteurii,12-h treatment cycle,and one pore volume of cementation media in each ***,a 24-h treatment cycle and 0.5-pore volume cementation solution were found to be the optimal treatment which was effective and economical to achiev