The Engineering Design And Construction Control Of Nanjing-Gaochun Long Distance Water Diversion Pipeline

With the continuous improvement of China’s urbanization,the risk of single water supply source in cities and the risk of lacking standard and clean drinking water in villages are becoming more and more prominent.The above problems can be effectively solved by selecting and constructing long-distance water transfer projects,which can scientifically and rationally allocating regional water resources.At present,many cities in China have been or are preparing to build long-distance water transmission projects.Based on the current status of water resources and the construction of the current regional water supply network,Nanjing has conducted targeted research on the longest and most invested water pipeline network in the long-distance Yangtze river water transport projects under construction in the city,especially the large-diameter water supply pipeline can be implemented in a new way of crossing through rivers,expressways and railways,as well as the construction organization,scheme comparison,pipe selection,pipe diameter determination,pipe interface,pipe corrosion and other technologies and key points.The research has played an important guiding role in the safety,economy and reliability of regional water supply in the city and surrounding areas.Based on the practice of Nanjing-Gaochun long-distance Yangtze river water diversion pipeline project,this paper systematically analyses and studies the design and construction difficulties of long-distance and large-caliber water purification pipeline project,which has strong theoretical guidance and practical application value.In this research,the design scale,water conveyance method and the determination and selection of water conveyance pipes involved in the design stage are discussed.Through the comparison and selection of multiple schemes,it is considered that the method of water diversion from the main city and water transportation is the most obvious economic benefit,which can solve the problem of water supply security in Gaochun district and the shortage of water supply in Lishui district.Single DN1400 pipe is used for water transmission,mainly ductile iron pipe,steel pipe or PE pipe can be used in special areas such as river channel and expressway ramp.According to different types of obstacles encountered in construction,different construction methods are analyzed and discussed in combination with engineering examples.For example,the pipeline of Yangtze river diversion project is laid along the outer side of the expressway,and excavation construction method is mostly adopted.Trenchless construction method(including pipe jacking and horizontal directional drilling)shall be adopted when the water supply pipeline passes through obstacles such as roads,expressways and rivers.Under special circumstances,such construction methods as open frame and sunken pipe can be adopted.