| Abstract: |
Coastal building construction faces severe challenges due to persistent groundwater seepage, driven by tidal fluctuations, hydrostatic pressure, and saline soil conditions that accelerate structural degradation. Conventional waterproofing materials such as bituminous membranes and cementitious coatings have demonstrated limited durability under the dynamic conditions prevailing in marine and estuarine environments. Polyurethane (PU) technology has emerged as a highly effective solution for groundwater seepage prevention owing to its exceptional elasticity, adhesion to diverse substrates, chemical resistance to saline water, and long-term impermeability. This review paper synthesizes existing literature on the application of polyurethane-based systems including spray-applied coatings, injection grouts, foam sealants, and hybrid composites in coastal construction scenarios. A meta-analysis of past experimental and field studies reveals consistent performance advantages of PU systems over conventional alternatives in terms of crack-bridging capacity, bond strength, and resistance to hydrostatic pressure. The paper critically evaluates methodological approaches, material formulations, and performance metrics employed across the reviewed studies. Findings indicate that two-component PU injection systems achieve pore closure efficiencies exceeding 95% in fractured substrates, while spray-applied membranes sustain waterproofing integrity for over 20 years under saline exposure. Research gaps concerning long-term environmental impact, bio-fouling, and temperature-driven degradation in tropical coastal zones are identified. This review provides engineers, architects, and construction professionals with a comprehensive evidence base for selecting and deploying polyurethane waterproofing technologies in coastal infrastructure projects. |
