Xiao Lei, Cheng Liang, Fang Dongyu
Papers # 2014 Chicago
The renovation of old water pipes in a big city, such as Shanghai in China, is always a challenging job due to huge population, heavy traffic and high demand for drinking water. Due to these problems No-Dig technology has become common practice, particularly relining using plastic pipes, to repair corroded metallic or concrete pipes. This paper describes the pipe renovation technology currently being used for drinking water supply pipelines and covers several real cases in China. This includes a recent project carried out by the Changzhou CGE Water Company which is responsible for the supply of fresh water to 2 million of local inhabitants. This case concerns the renovation of a leaking large diameter (1000mm diameter) cast iron main, which is buried 3.5 meter under a high speed railway bridge. Continued leakage of this main would erode the soil which could potentially damage the foundations of the bridge. One effective solution for the leakage of the corroded iron water main is to insert a close-fit PE100 pipe into the bore of the main. It is the first project in such a large size for both engineering and water companies in China. This solution is attractive in terms of both of economic and environmental aspects causing the least disturbance to the neighborhood. However there are a number of challenges including the jointing and forming process and the potential damage to the outer surface of the PE pipe. The success on this project has subsequently been shared with other water companies who are facing with similar problems in China.