Impact of Hybrid UV Photo Curing with Rechargeable Electricity on Trenchless Rehabilitation of Sewage Pipelines

Sewage pipes with structural defects cause ground subsidence owing to the occurrence of cavities, and trenchless rehabilitation is the primary repair method. Most trenchless rehabilitation uses the cured-in-place pipe (CIPP) method with a tube liner. UV photo curing has recently gained prominence for solving problems such as construction quality and high energy consumption associated with conventional thermal curing methods. This study developed a glass fiber tube liner and a hybrid power supply system with a uninterruptible power supply (UPS) and batteries to improve construction quality and shorten construction time when using UV photo curing. The tube liner had a flexural strength of 236.3 MPa and a flexural modulus of 10.5 GPa. These results are 7.88 and 6.2 times higher than the KS M3550-9 standards of 30 MPa and 1.7 GPa, respectively. Therefore, improved construction quality and post-construction sewage pipe lifespan were expected. A field test of construction with UV photo curing, using the glass fiber tube liner and the hybrid power system developed in this study, demonstrated successful performance in terms of power supply stability, UV photo-curing efficiency, and construction quality. Total working time was 121 min for construction of a 50 m section of the D600 using CIPP, significantly reducing construction time compared to conventional UV photo-curing technology.