Work

Cement-Induced Alkaline Environment on Organic Soil: Deterioration, Compensation, and the Microstructure-Mechanical Property Relationship

Year: 2026

Type: article

Abstract: In the cement-based stabilization of organic soil, the alkaline environment produced by cement hydration dissolves organic matter from the soil skeleton while simultaneously promoting the precipitation of neophases. This study investigates the coupled effects of structural deterioration and neophase compensation on the microstructural and mechanical properties of organic soil. Organic soil was treated with an alkaline Ca(OH)2 solution (pH = 12.0) utilizing a model testing apparatus over an 80-day duration. Consolidation and permeability tests were combined with microstructural analyses (FTIR, XRD, and SEM-EDS) to elucidate the fundamental mechanisms. The results show that humus acid in organic soil was dissolved in an alkaline environment, significantly enlarging soil pores and forming interconnected dissolution channels. Consequently, the permeability coefficient and additional settlement increased by 49.21% and 18.07%, respectively, compared to the pristine soil samples. Concurrently, within the OH−-and Ca2+-rich environment, clay minerals underwent a pozzolanic reaction, generating C-(A)S-H gels. Dissolved humus acid formed complexes with Ca2+ ions. While these formed neophases provide microstructural compensation for the organic soil, their compensatory effect is limited. These findings provide a critical theoretical framework for understanding the coupled deterioration–compensation mechanisms, which is essential for optimizing engineering design and promoting the long-term durability of alkaline-reinforced organic geotechnical environments.

Source: Applied Sciences

DOI: 10.3390/app16094324

Authors: Yongfei Zhang, Jing Cao, Dequan Song, Lingyi Zhang, Song Lan, Siyang Huang

Institution: Kunming University of Science and Technology

Language: English

Topic: Geotechnical Engineering and Soil Stabilization

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Life on land

Open Access status: gold

Estimated APC paid: $2,896