Study On Large Channel Construction Technology Of The Middle Route Of South-to-north Water Transfer Project

Currently,the Middle Route of South-to-North Water Transfer Project is the largest water diversion project, water main canal total length is 1277 km, the length of main canal supplying water to Tianjin is 154 km. the available water of annual average amount is 14.14 billion m3. Channel design discharge is 330 m3/s, enlarged flow quantity is 400 m3/s. At the same time, the difficulty of its construction in many aspects is also located in the domestic construction of similar projects, including large-scale channel has the construction long period, the unfavorable geological factors such as climate, weather, groundwater, expansive soil have great impact. How to solve the negative impact of the above factors on the construction, it is the heavy and difficult problem of this construction.In this paper, considering these objective factors, through Ye county I bid section large channel construction and a comprehensive and detailed analysis, the specific operation measures were put forward. The detailed description of surface water and groundwater treatment construction technology, the modified soil filling construction process, the lining and the drainage system construction technology and the seepage analysis and control of the stratified and rolled channel slope. And causes of the channel common construction quality defects were analyzed, summarized and put forward specific measures to deal with preventive measures.Firstly, the surface and ground water closure and drainage measures from the excavation and construction of channel, and channel modified soil filling foundation surface, introduced in detail layout form and the construction process of the permanent groundwater seepage control measures; The construction of expansive soil mainly describes the filling construction process of modified soil, how to solve channels foundation bed expansive soil cause the dangers of canal lining, and how to modify material sources expansive soil to cement soil, and a detailed description of the modified soil construction process principles, process, methods and precautions and quality assurance measures;The lining construction technology of large channel mainly from the construction process, a detailed description of the canal bed arrange, the lining construction of the drainage system, geomembrane laying, the lining thin-wall concrete construction technology using the lining machine, etc. Summarizes the control measures of quality taken by the various construction aspects as well as preventive measures to deal with the impact of construction caused by unusual weather, and the the lining the common quality defects were summarized, analyzed its causes, and proposed specific targeted treatment measures; The analysis and control of the filled channel slope with stratified and rolled, introduces the conversion of different soil layers permeability coefficient, and a finite element model is created for the corresponding theoretical calculation and analysis.In short, the current construction technology of the domestic large-scale channels in many aspects are still exploring the practice, especially in the face groundwater rich and expansive soil, etc. unfavorable geological conditions, the further research needs to be treatment measures taken. In this paper, the construction of Middle Route of South-to-North Water Transfer Project’s large channels based, describes in detail how the large-scale channels construction treat adverse geological conditions, and comprehensively analyzes and describes construction technique, design and construction of similar projects have certain reference.