Desiccation Cracking Behavior of MICP-Treated Bentonite

Autor: Mark Vail, Cheng Zhu, Chao-Sheng Tang, Luke Anderson, Michael Moroski, Melissa Tabada Montalbo-Lomboy
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Geosciences, Vol 9, Iss 9, p 385 (2019)
Druh dokumentu: article
ISSN: 2076-3263
DOI: 10.3390/geosciences9090385
Popis: This study aims to characterize the effect of microbial-induced calcite precipitation (MICP) on the desiccation cracking behaviors of compacted calcium bentonite soils. We prepare six groups of samples by mixing bentonites with deionized water, pure bacteria solution, pure cementation solution, and mixed bacteria and cementation solutions at three different percentages. We use an image processing tool to characterize the soil desiccation cracking patterns. Experimental results reveal the influences of fluid type and mixture percentage on the crack evolution and volumetric deformation of bentonite soils. MICP reactions effectively delay the crack initiation and remediate desiccation cracking, as reflected by the decreased geometrical descriptors of the crack pattern such as surface crack ratio. The mixture containing 50% bacteria and 50% cementation solutions maximizes the MICP treatment and works most effectively in lowering the soil cracking potential. This study provides new insights into the desiccation cracking of expansive clayey soils and shows the potential of MICP applications in the crack remediation.
Databáze: Directory of Open Access Journals