Trenchless Mechanized Inspection and Retrofitting Strategy for Buried Sewerage Systems

The conventional retrofitting methods of buried sewer pipes require heavy machinery, intensive manpower, and a longer time for rehabilitation. Such methods may also damage the nearby infrastructures and landscapes. The present study explores an integrated trenchless solution for damage identification and mechanized retrofitting of domestic buried sewerage pipelines of diameter ranging from 75 to 300 mm. A front-mounted camera of the retrofitting system assesses the damage inside the sewer pipes. The retrofitting of the damaged part of buried pipe is achieved by impregnation of Glass Fiber Reinforced Polymer (GFRP) composite sheet with 100:16 epoxy and hardener ratio. The wrapping of the GFRP sheets on damaged part is done by inflation and deflation technique with a cylindrical rubber bladder connected by a flexible shaft. The retrofitted sewer pipe can be resumed after 3–4 hours of applying the impregnated GFRP composite with above retrofitting strategy.