ENHANCED SOIL PILES WITH PORTLAND CEMENT-RHA-MWCNT MIX FOR DEEP MIXING METHODS IN LOW-RISE BUILDING AND BRIDGE FOUNDATIONS

Soft soil's low strength and high deformation characteristics pose significant challenges in low-rise building and bridge constructions. This research introduces an innovative method to fortify soft soil using Portland cement (PC), rice husk ash (RHA), and multi-walled carbon nanotubes (MWCNTs) as additives for reinforced soil pile (RSP) development through a deep mixing technique. The physico-mechanical characterization result reveals a remarkable 83% (1075 to 1962 kg/m3) increase in average density and a significant 405% (4.14 to 20.92 MPa) enhancement in compressive strength after 28 days of curing, achieved with the addition of only 0.04 wt% MWCNT to the soil-PC-RHA mixture. Furthermore, a large-scale static load test was conducted to assess its translational efficiency in a real-world scenario. The result revealed a comparable compressive strength between the laboratory-scale and large-scale implementation (20.9 MPa vs. 23.4 MPa). This substantial improvement, attributed to the synergistic effects of MWCNT, surpasses the performance of traditional soil-PC-RHA blends in the literature. By leveraging the distinctive attributes of PC, RHA, and MWCNT, this eco-friendly technology offers a promising alternative for high-strength low-rise construction, addressing the inherent limitations of soft soils and presenting transformative potential with far-reaching implications for geotechnical engineering and sustainable infrastructure development.