Abstract

Reinforced Earth (RE) walls are widely used in infrastructure due to their structural efficiency and ease of construction. However, they typically require high-quality granular backfill, which may not be readily available or cost-effective in many regions. This study investigates the potential of utilizing locally available sandy clay soil stabilized with industrial and plastic waste materials specifically 20% steel slag and 0.75% shredded polyethylene terephthalate (PET) fibers, as an alternative backfill for reinforced Earth (RE) walls. A comprehensive laboratory testing program was conducted to evaluate the geotechnical properties of the stabilized soil. Results showed substantial improvements in mechanical behavior: unconfined compressive strength increased to 440 kPa, California Bearing Ratio (CBR) rose from 4% to 16%, and plasticity index was reduced to non-plastic, indicating enhanced strength, stiffness, and workability.To validate the laboratory findings, a full-scale 6-meter-high RE wall was constructed using the optimized soil mix. Field monitoring over time recorded minimal vertical settlement (~7 mm) and very low lateral deflection (~3 mm), confirming the structural integrity and stability of the wall. The performance met the design requirements in accordance with Indian Roads Congress (IRC) specifications.This study demonstrates that the proposed soil-steel slag- polyethylene terephthalate fiber composite is a technically viable and sustainable alternative backfill material for RE wall applications. In addition to providing satisfactory engineering performance, it promotes the reuse of industrial by-products and plastic waste, offering both environmental and economic benefits. The findings support the use of such composites in future infrastructure projects to foster more sustainable construction practices.

Keyword: PET fiber, slag stabilization, composite material, reinforced soil, polymer reinforcement, RE wall backfill

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Refrences:

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