Construction of road pavement generates instability to the natural subsoil which encounters numerous engineering problems such as settlement, depression, sinkhole and faulting of subsoil. The conventional method of soil remediation work in subsoil such as crack sealing, patching potholes, overlays and grouting technique provide short term solutions to address those symptoms, but not the underlying problem. This study permits a novel method to solve the subsoil foundation problem precisely in the sand that exists in the current pavement designs using Polyurethane (PU) grout. PU is a chemical substance that generally used in polymer industries, for instance, resilience foam seating, rigid foam insulation panels and microcellular foam seals. The study includes four main parts: the first part aims to optimize the composition of PU by varying the mixture of polyol and isocyanate under Unconfined Compression Test (UCT). Conclusively, this study has presented reliable results and predictions on the behaviour of treated sand with PU and an alternative remediation method whereby its shorten the time of implementation and eliminate the excavation works. In conclusion, this study can contr