Effect of drying-wetting cycles on pore characteristics and mechanical properties of enzyme-induced carbonate precipitation-reinforced sea sand  

作　　者：Ming Huang Kai Xu Zijian Liu Chaoshui Xu Mingjuan Cui 

机构地区：[1]College of Civil Engineering,Fuzhou University,Fuzhou,350108,China [2]Xiamen Rail Transit Construction and Development Group Co.,Ltd.,Xiamen,361000,China [3]School of Civil,Environment and Mining Engineering,The University of Adelaide,Adelaide,5005,Australia

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第1期291-302,共12页岩石力学与岩土工程学报（英文版）

基　　金：The authors gratefully acknowledge the financial support of National NaturalScience Foundation of China(Grant No.41972276);Natural Science Foundation of Fujian Province,China(Grant No.2020J06013);"Foal Eagle Program"Youth Top-notch Talent Project of Fujian Province,China(Grant No.00387088).

摘　　要：Enzyme-induced carbonate precipitation(EICP)is an emanating,eco-friendly and potentially sound technique that has presented promise in various geotechnical applications.However,the durability and microscopic characteristics of EICP-treated specimens against the impact of drying-wetting(D-W)cycles is under-explored yet.This study investigates the evolution of mechanical behavior and pore charac-teristics of EICP-treated sea sand subjected to D-W cycles.The uniaxial compressive strength(UCS)tests,synchrotron radiation micro-computed tomography(micro-CT),and three-dimensional(3D)recon-struction of CT images were performed to study the multiscale evolution characteristics of EICP-reinforced sea sand under the effect of D-W cycles.The potential correlations between microstructure characteristics and macro-mechanical property deterioration were investigated using gray relational analysis(GRA).Results showed that the UCS of EICP-treated specimens decreases by 63.7% after 15 D-W cycles.The proportion of mesopores gradually decreases whereas the proportion of macropores in-creases due to the exfoliated calcium carbonate with increasing number of D-W cycles.The micro-structure in EICP-reinforced sea sand was gradually disintegrated,resulting in increasing pore size and development of pore shape from ellipsoidal to columnar and branched.The gray relational degree suggested that the weight loss rate and UCS deterioration were attributed to the development of branched pores with a size of 100-1000 m m under the action of D-W cycles.Overall,the results in this study provide a useful guidancee for the long-term stability and evolution characteristics of EICP-reinforced sea sand under D-W weathering conditions.

关 键 词：Enzyme-induced carbonate precipitation(EICP) Plant-based urease Drying-wetting(D-W)cycles Microstructure 

分 类 号：TU45[建筑科学—岩土工程]