Assessment Methods and Progress of Fitness-for-service for Polyethylene Pipes after Fire Damage

After a fire accident, the nonmetal pipe near the fire ground will be affected by the fire or the heat, which may cause damage or performance deterioration of the pipe. The safety assessment of fire damaged pipe involves fitness-for-service assessment technique. However, the existed standards and specifications of fitness-for-service assessment are almost all about metallic materials. There is little fitness-for-service assessment research concerning polymer materials and polymer pipes at home and abroad. In this paper, the commonly used assessment standards and specifications of structure integrity of components after heating were summarized. The assessment method and characterization method of polyethylene pipes were proposed through analysis and comparison.