Expansive soil modified by iron tailing sand and calcium carbide slag as subgrade material

Chengfu Chu (), Meihuang Zhan (), Qi Feng (), Yongfeng Deng (), Dong Li (), Fusheng Zha () and Xiaoliang Hou ()
Additional contact information
Chengfu Chu: Hefei University of Technology
Meihuang Zhan: Hefei University of Technology
Qi Feng: Hefei University of Technology
Yongfeng Deng: Southeast University
Dong Li: Hefei University of Technology
Fusheng Zha: Hefei University of Technology
Xiaoliang Hou: Hefei University of Technology

Environment, Development and Sustainability: A Multidisciplinary Approach to the Theory and Practice of Sustainable Development, 2023, vol. 25, issue 9, No 59, 10393-10410

Abstract: Abstract Expansive soil encounters large changes in strength and volume with the water content alteration for rich in hydrophilic montmorillonite minerals. It can be physically/chemically modified to suppress the water sensitivity by mixing with recycled industrial by-products (iron tailing sand and calcium carbide slag in this case) as the backfilling material of subgrades for the engineering practices. The specimens were prepared with 30% iron tailing sand and 6–12% calcium carbide slag. Atterberg consistency limit, the free swelling index, loaded swelling rate, unconfined compressive strength, water stability, and microstructure were determined at the preset curing times. The results showed that after modification, the free swelling index decreased to below 30%, satisfying the requirements for the expressway subgrade. The loaded swelling rate was negative under loading and soaking condition, indicating compressibility. The compressibility was evident from the peak value with a calcium carbide slag content of 10%, and a similar trend was observed for the evolution of unconfined compressive strength. With the increase in calcium carbide slag content, the water stability coefficient of modified soil also increases. The pore size distribution was of typical bi-modal characteristics, and the modification just dominated the large porosity. The microstructure was the densest, and the fewest inter-aggregate pore volume was observed at the calcium carbide slag optimal content, 10%.

Keywords: Expansive soil; Calcium carbide slag; Iron tailing sand; Swelling potential; Subgrade backfilling material (search for similar items in EconPapers)
Date: 2023
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://link.springer.com/10.1007/s10668-022-02498-x Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:spr:endesu:v:25:y:2023:i:9:d:10.1007_s10668-022-02498-x

Ordering information: This journal article can be ordered from
http://www.springer.com/economics/journal/10668

DOI: 10.1007/s10668-022-02498-x

Access Statistics for this article

Environment, Development and Sustainability: A Multidisciplinary Approach to the Theory and Practice of Sustainable Development is currently edited by Luc Hens

More articles in Environment, Development and Sustainability: A Multidisciplinary Approach to the Theory and Practice of Sustainable Development from Springer
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().