Development of the trenchless rehabilitation process for underground pipes based on RTM

In order to overcome the disadvantages of conventional excavation technology for repairing and replacing worn-out underground pipes, various trenchless technologies have been developed and tried. But trenchless technologies so far developed have some drawbacks such as high cost and inconvenience of operation. In this study, a rehabilitation process for underground pipes has been developed using vacuum assisted resin transfer molding (VARTM) with glass fiber fabric preform to overcome the disadvantages of present trenchless technologies. For the reliable operation of the developed method, a simple method to apply pressure and vacuum to the reinforcement was devised with a flexible mold technology. From the investigation, it has been found that the developed process requires shorter operation time and lower cost with smaller and simpler operating equipments than those of the conventional trenchless technologies. Keywords