Predictive Assessment of Long-Term Hydrostatic Strength of HDPE Pipes Under Elevated Temperatures: A Modelling and Experimental Approach

High-density polyethylene (HDPE) pipes are widely applied in water distribution, natural gas transport, and industrial networks owing to their superior toughness, chemical resistance, and ease of installation. However, evaluating their long-term hydrostatic strength (LTHS) using conventional methodologies such as ASTM D2837 and ISO 9080 requires extensive testing periods of up to 10,000 hours, making it impractical for rapid qualification of new materials and designs. This study develops an accelerated predictive methodology combining short-term hydrostatic pressure tests at elevated temperatures (50°C, 60°C, and 80°C) with time–temperature superposition (TTSP), Arrhenius modeling, and Eyring-based approaches to predict lifetime performance under service conditions (20–40°C). Fifteen HDPE specimens were tested, and regression-based extrapolations were carried out. Results indicate that higher test temperatures accelerate failure times in accordance with thermally activated processes, enabling reliable extrapolation to 50-year design lives. The integrated models improve prediction accuracy compared with TTSP alone, and the findings are particularly relevant to hot-climate applications where temperature sensitivity becomes critical.