Effects of microbially induced calcite precipitation (MICP) on the soil-concrete interface behavior

Document Type

Conference Proceeding

Publication Date

2025

Department

Department of Civil, Environmental, and Geospatial Engineering

Abstract

Improving the shear strength at the soil-concrete interface can enhance the capacity of structures in various applications, such as horizontal sliding of footings, retaining walls, side friction capacity of pile foundations, and seismic design of tunnel linings. Choosing a sustainable, economical, and environmentally friendly approach is necessary when it comes to engineering practices. To achieve such an approach, the effectiveness of microbially induced calcite precipitation (MICP) in improving the soil-concrete interfacial shear strength was investigated in this study. Soil samples in contact with concrete were treated using the two major MICP pathways, i.e., ureolysis and denitrification. The required microorganisms for both pathways were cultivated from the activated sludge obtained from a wastewater treatment facility. MICP treatment can potentially improve the interface properties through different mechanisms, i.e., bonding the soil particles to the concrete, changing the roughness of the soil particles, and filling the pores between the soil and concrete. The effectiveness of the treatment would also depend on the soil gradation. Therefore, a poorly graded dune sand and a well-graded silty sand were used in this study. A series of laboratory direct shear tests were conducted on both treated and untreated samples. The results of the tests are presented and the effects of MICP pathways, soil gradation, and different contributing mechanisms are discussed.

Publication Title

2025 International Conference on Bio-mediated and Bio-inspired Geotechnics (ICBBG2025)

Link to Full Text

Share

COinS