Abstract:
The increasing demand for infrastructure development on suboptimal soils, particularly soft clays, has
necessitated innovative ground improvement techniques. This study evaluates the effectiveness of
Recycled Asphalt Pavement (RAP)-infused granular piles in enhancing the load-bearing capacity and
settlement performance of soft clay beds. Utilizing both Ordinary Floating Granular Piles (OGP) and
Encased Floating Granular Piles (EGP) with geotextile, a series of load-settlement tests were conducted
to assess their suitability for soft soil reinforcement under varying mix proportions.
The results reveal that the integration of RAP with stone aggregates significantly improves the
mechanical properties of soft soils, with the optimal performance achieved using a 50% Stone - 50%
RAP (50S-50R) mixture. This configuration demonstrated the highest ultimate bearing capacity and
minimal settlement, effectively balancing the stiffness and strength of stone with the energy absorption
and flexibility of RAP. Furthermore, the use of geotextile-enclosed granular piles (EGP) markedly
enhanced performance by minimizing lateral bulging, optimizing load distribution, and further reducing
settlement, with the 50S-50R (EGP) configuration achieving the most superior results.
Comparative analysis indicates that configurations with higher RAP content (e.g., 75R-25S and 100R)
are less effective due to the inherently lower stiffness of RAP; however, their performance improves
significantly when combined with geotextile. This underscores the critical role of geotextile in enabling
more effective load transfer and settlement control, particularly for sustainable construction practices.
Overall, this research establishes RAP-infused granular piles, particularly when combined with
geotextile enclosures, as a viable and sustainable solution for enhancing the load-carrying capacity of
soft soils. The findings contribute to the advancement of geotechnical engineering by providing
evidence-based insights into the use of recycled materials for ground improvement, promoting both
environmental sustainability and economic efficiency in construction practices.
Description:
Supervised by
Dr. Hossain Md Shahin,
Professor,
Department of Civil and Environmental Engineering (CEE)
Islamic University of Technology (IUT)
Board Bazar, Gazipur, Bangladesh