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Application of recycled concrete aggregate for stabilizing laterite soil |
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| รหัสดีโอไอ | |
| Title | Application of recycled concrete aggregate for stabilizing laterite soil |
| Creator | Syaifulloh Qoimuddin |
| Contributor | Amin Eisazadeh Otaghsaraei, Advisor |
| Publisher | Thammasat University |
| Publication Year | 2567 |
| Keyword | Laterite soil, Recycled concrete aggregate, Lime, Compaction, UCS, Shear strength, CBR, Permeability test |
| Abstract | The increasing urgency for sustainable development, driven by challenges such as global warming and extreme weather, necessitates innovative solutions in construction practices. Construction and demolition waste (CDW) recycling is a pivotal strategy to address environmental concerns while conserving natural resources. This study investigates the use of recycled concrete aggregate (RCA) and lime as stabilizers for improving the engineering properties of laterite soil (LS), a material commonly employed in road construction in Thailand but often deficient in required subgrade properties. RCA, a byproduct of demolition waste, offers potential as a sustainable alternative to natural aggregates. A series of laboratory tests, including compaction, unconfined compressive strength (UCS), direct shear, California Bearing Ratio (CBR), and permeability tests, were conducted on various mix designs comprising LS, RCA, and lime. The results demonstrated that incorporating 45% RCA and 6% lime yielded the highest UCS and CBR values, meeting the Department of Highways (DOH) standards for subbase materials. UCS tests revealed a 7.1-fold strength increase in lime-treated mixtures after 56 days of curing, with the formation of calcium silicate hydrate (C-S-H) gels confirmed through FESEM and EDS analyses. This microstructural improvement was attributed to the pozzolanic reactions and cementitious properties of RCA and lime. Furthermore, the addition of RCA enhanced soil gradation, reduced plasticity, and increased permeability, while lime mitigated water absorption and further stabilized the soil structure. These findings highlight the efficacy of RCA and lime in transforming laterite soil into a sustainable and cost-effective construction material, contributing to environmentally responsible infrastructure development in Thailand and beyond. |
