USE OF SHREDDED PURE WATER SACHETS (LPDE) IN STABILIZING LATERITIC SOIL FOR ROAD CONSTRUCTION

This research addresses a critical dual problem in Nigeria: the premature failure of road infrastructure due to the poor geotechnical properties of locally abundant lateritic soil and the severe environmental pollution caused by carelessly discarded Low-Density Polyethylene (LDPE) pure water sachets. This plastic waste, being non-biodegradable, clogs vital drainage systems, exacerbating seasonal flooding and creating long-term hazards by breaking down into harmful microplastics. The project seeks to provide a sustainable and cost-effective alternative to traditional, resource-intensive stabilizers like cement and lime. The core objective is to determine the effectiveness of utilizing shredded LDPE sachets as a stabilizing additive to enhance the engineering properties of lateritic soil for road construction. The methodology involves collecting and processing lateritic soil and waste LDPE sachets, which are then blended at varying proportions: 0%, 2%, 4%, and 6% by weight of the soil. Standard geotechnical tests, strictly following BS 1377 (1990) procedures. The unsoaked CBR value increased by approximately 227%, rising from 3.8% at 0% plastic content to 12.69% at 6% content. Similarly, the soaked CBR value improved by 93.5% increasing from 4.91% to 9.50%. These results demonstrate that the modified soil at 6% stabilization meets the standard requirements for road subgrade materials, offering a superior alternative to unstable lateritic soil. In conclusion, the results of this investigation demonstrate that incorporating waste LDPE sachets into lateritic soil successfully improves its engineering performance. This approach presents a pragmatic, two-pronged solution that simultaneously addresses a pervasive national pollution problem and offers a sustainable, cost-effective method for strengthening Nigeria’s essential road infrastructure, leading to a longer service life for flexible pavements.