Effect of fiber type and content on mechanical properties of microbial solidified sand

Frontiers in Materials

Materials

Xiaogang Zhang¹  Kun Yang¹  Chao Zheng¹  Kangwei Xiong¹  Shihua Liang² 

[1] Guangzhou Environmental Protection Investment Company Limited, Guangzhou, China;School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, China;

关键词: MICP;    content of fibers;    mechanical properties;    type of fibers;    CaCO content;   

DOI  :  10.3389/fmats.2023.1218795

 received in 2023-05-08, accepted in 2023-09-06,  发布年份 2023

来源: Frontiers

【 摘 要 】

Fibers are applied to construction works to improve the strength and brittle failure of the soil. In this paper, fibers with a length of 6 mm are added to the microbial cemented sand, and fiber types and content are research variable. Unconfined compressive strength (UCS), permeability coefficient, water absorption rate, dry density, and calcium carbonate precipitation of the solidified sand were tested. The physical and mechanical properties of fiber types and content on the immobilization of microorganisms were also analyzed from the micro–macro perspective. Results are presented as follows. The UCS of the Microbial induced calcium carbonate precipitation (MICP) treated sand increases first and then decreases with the increasing fiber content. This phenomenon is due to the promotion of calcium carbonate precipitation by short fiber reinforcement, the limited movement of the sand particles caused by the formed network between the fibers, and the enhanced strength of the microbial solidified sand. However, the agglomeration caused by additional fibers leads to the uneven distribution of calcium carbonate and the reduction in strength. The optimum fiber contents of polypropylene, glass, polyvinyl alcohol, and basalt fibers are 0.4%, 0.2%, 0.2%, and 0.1%, respectively.

【 授权许可】

Unknown   
Copyright © 2023 Zhang, Zheng, Xiong, Yang and Liang.