Sustainable Stabilisation of Expansive Clay with Shredded PET Fibers: Multi-Scale Performance and Microstructural Analysis

Thatikonda Naresh (), Sandeep Bandipally, Nannuta Satya Shiva Prasad, Krzysztof Skrzypkowski (), Krzysztof Zagórski and Anna Zagórska
Additional contact information
Thatikonda Naresh: Department of Civil Engineering, ACE Engineering College, Hyderabad 500001, India
Sandeep Bandipally: Department of Civil Engineering, ACE Engineering College, Hyderabad 500001, India
Nannuta Satya Shiva Prasad: Department of Civil Engineering, Kakathiya University, Warangal 506381, India
Krzysztof Skrzypkowski: Faculty of Civil Engineering and Resource Management, AGH University of Krakow, Mickiewicza 30 Av., 30-059 Kraków, Poland
Krzysztof Zagórski: Faculty of Mechanical Engineering and Robotics, AGH University of Krakow, Mickiewicza 30 Av., 30-059 Kraków, Poland
Anna Zagórska: Research Centre in Kraków, Institute of Geological Sciences, Polish Academy of Science, Senacka 1, 31-002 Kraków, Poland

Resources, 2025, vol. 14, issue 11, 1-23

Abstract: Expansive clay soils present major challenges for infrastructure due to their high swelling potential and low bearing capacity. While conventional stabilisers, such as lime and Ordinary Portland Cement (OPC), are effective, they are environmentally unsustainable due to their high carbon footprint. This study examines the potential of shredded recycled polyethene terephthalate (PET) fibres as a low-carbon alternative for stabilising high-plasticity clays. PET fibres were incorporated at dosages ranging from 0% to 1.2% by dry weight, and their influence on compaction characteristics, unconfined compressive strength (UCS), California Bearing Ratio (CBR), swelling behaviour, and microstructure was evaluated through laboratory testing and Scanning Electron Microscopy (SEM). Among the tested mixes, the 1.0% PET content exhibited the highest measured performance, resulting in a 37% increase in UCS, a 125% enhancement in unsoaked CBR, more than a two-fold increase in soaked CBR, and a 15% reduction in the Differential Free Swell Index (DFSI). SEM analysis indicated the formation of a three-dimensional fibre matrix, which improved particle interlock and reduced microcrack propagation. However, higher fibre dosages caused agglomeration and macrovoid formation, which adversely affected performance. Overall, the findings suggest that the inclusion of PET fibres can enhance both geotechnical and environmental performance, providing a sustainable stabilisation strategy that utilises plastic waste while reducing reliance on OPC.

Keywords: expansive soils; recycled PET fibres; sustainable soil stabilisation; unconfined compressive strength; California bearing ratio; swell mitigation; circular economy; resource valorisation (search for similar items in EconPapers)
JEL-codes: Q1 Q2 Q3 Q4 Q5 (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2079-9276/14/11/174/pdf (application/pdf)
https://www.mdpi.com/2079-9276/14/11/174/ (text/html)

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:gam:jresou:v:14:y:2025:i:11:p:174-:d:1792253

Access Statistics for this article

Resources is currently edited by Ms. Donchian Ma

More articles in Resources from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().