Dounia Azerkane, Meriam El Ouahabi, Achraf Harrou, Faiçal El Khazanti, El Khadir Gharibi
{"title":"Potential use of phosphogypsum as an additive for stabilizing soft kaolinite soils: enhancement of the foundation layer","authors":"Dounia Azerkane, Meriam El Ouahabi, Achraf Harrou, Faiçal El Khazanti, El Khadir Gharibi","doi":"10.1007/s10163-025-02216-5","DOIUrl":null,"url":null,"abstract":"<div><p>The shear resistance of clayey soils can be improved through chemical stabilization with hydraulic lime. This study examines the stabilization of soft kaolin clayey soils by adding phosphogypsum (PG) waste and lime. This approach reuse of PG waste, typically stored in piles, by integrating it into kaolin-rich soils to improve their stability. Structural, microscopic, geotechnical, and mechanical characterization techniques were employed to enhance the understanding of soil stabilization mechanisms and their potential applications in road construction. Kaolinite lacks pozzolanic reactivity with lime, but crystalline and amorphous aluminosilicates in the soil facilitate the formation of calcium silicate hydrate (CSH) gel, which binds soil particles cohesively. The addition of PG to the soil-lime mixture allows soil stabilization through the formation of ettringite and CSH gel, and the crystalline needle-like of phosphogypsum. The mechanical compressive strength increases from 0.35 MPa for raw earth mortar consisting of 90% soil and 10% lime to 0.80 MPa for a mixture consisting of 68% soil, 10% lime and 32% PG. The compressive mechanical strength obtained by adding PG to kaolin clay exceeds the minimum threshold of 0.66 MPa required for the structural design of road pavements.</p></div>","PeriodicalId":643,"journal":{"name":"Journal of Material Cycles and Waste Management","volume":"27 3","pages":"1691 - 1707"},"PeriodicalIF":2.7000,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Material Cycles and Waste Management","FirstCategoryId":"93","ListUrlMain":"https://link.springer.com/article/10.1007/s10163-025-02216-5","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
The shear resistance of clayey soils can be improved through chemical stabilization with hydraulic lime. This study examines the stabilization of soft kaolin clayey soils by adding phosphogypsum (PG) waste and lime. This approach reuse of PG waste, typically stored in piles, by integrating it into kaolin-rich soils to improve their stability. Structural, microscopic, geotechnical, and mechanical characterization techniques were employed to enhance the understanding of soil stabilization mechanisms and their potential applications in road construction. Kaolinite lacks pozzolanic reactivity with lime, but crystalline and amorphous aluminosilicates in the soil facilitate the formation of calcium silicate hydrate (CSH) gel, which binds soil particles cohesively. The addition of PG to the soil-lime mixture allows soil stabilization through the formation of ettringite and CSH gel, and the crystalline needle-like of phosphogypsum. The mechanical compressive strength increases from 0.35 MPa for raw earth mortar consisting of 90% soil and 10% lime to 0.80 MPa for a mixture consisting of 68% soil, 10% lime and 32% PG. The compressive mechanical strength obtained by adding PG to kaolin clay exceeds the minimum threshold of 0.66 MPa required for the structural design of road pavements.
期刊介绍:
The Journal of Material Cycles and Waste Management has a twofold focus: research in technical, political, and environmental problems of material cycles and waste management; and information that contributes to the development of an interdisciplinary science of material cycles and waste management. Its aim is to develop solutions and prescriptions for material cycles.
The journal publishes original articles, reviews, and invited papers from a wide range of disciplines related to material cycles and waste management.
The journal is published in cooperation with the Japan Society of Material Cycles and Waste Management (JSMCWM) and the Korea Society of Waste Management (KSWM).