Water pressure test in the design of the tunnel in Yellow River crossing project of the mid-route of South-to-north water transfer project

2015 ◽  
pp. 69-76
Author(s):  
Jun Zhou ◽  
Tao Deng ◽  
Guangchuan Liang ◽  
Jinghong Peng ◽  
Tian Meng ◽  
...  

Abstract Pigging techniques are widely used in the oil and gas industry. The unsteady motion of the PIG in an undulating pipe section during the pigging process after a water pressure test affects the stable operation of the pipeline and also causes a pipe rupture accident in serious cases. First, an experimental study was conducted to investigate the pigging process of air–water two phase pipe flows, and the PIG reverse movement and hydraulic pulse phenomenon were observed. Subsequently, a hydraulic transient model of the pigging process after a water pressure test was established in a dual-grid system. The model combined mass and motion equations of gas and liquid and PIG dynamic equations, considered three types of PIG motion states, namely positive movement, reverse movement and still, and used the method of characteristics to solve the equations. The model exhibits the ability for PIG tracing and hydraulic pulse prediction. It can be used to obtain the position and speed of the PIG. Finally, the field data and simulation results were compared, and the results indicated that they are essentially identical. This verified the accuracy of the model that is established in this study and the reliability of computed results and provided a reliable and effective theoretical basis for the development of field pigging plans.


2011 ◽  
Vol 250-253 ◽  
pp. 1212-1216
Author(s):  
Da Hu Rui ◽  
Qing Hong Wu ◽  
Zhen Feng Cao ◽  
Yu Xia Zhao ◽  
Guang Fan Li

Yellow River-Crossing Project in South-to-North Water Transfer approach through the use of shield tunnel and its north bank departure shaft adopts diaphragm wall as enclosure structure. The depth of continuous wall of its shielding starting shaft is 76.6m, which is the deepest at present in china. The continuous diaphragm wall travels through the layer of silver sand, medium sand and loam from top to bottom, where the geological conditions are poor with large difficulty of construction. This paper sets forth construction of guide wall, reinforcing measures before construction, Trenching process, groove segment connections, innovative technologies of uplifting huge reinforcing cage and so on, which will provide guidance and lessons for the similar project


2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Wei Chen ◽  
Datian Cui ◽  
Meng Xu ◽  
Rongchao Xu

The water pressure test and steady-flow pumping test are still commonly used for measuring the permeability coefficient of rock and soil strata. Limited by the fact that the average value of the permeability coefficient could be obtained only by this testing method, the accuracy of the experimental results of the permeability coefficient for special rock and soil strata is not good. Therefore, a new on-site testing method and equipment for continuously measuring the permeability coefficient of rock and soil strata is studied in this paper. The method is suitable for water pressure testing in borehole and the steady-flow pumping test. The technical proposal is when the pumping test or water pressure test is carried out, the final water penetration will tend to be a stable value, and then, the high-precision current meter probe will be placed at the bottom of the pumping test hole or water pressure test hole. For the pumping test, the current meter will be lifted uniformly from the bottom of the borehole testing section to the stable water level. Meanwhile, the flow rate of a differential zone of the tested section is continuously detected. For the water pressure test, the current meter will be lifted uniformly from the bottom of the borehole test section to the top of the borehole test section, and the flow rate of the differential section will be continuously detected. Through data analysis and processing, not only the average permeability coefficient of the detected sections can be obtained but also the permeability coefficient of the differential section of the rock and soil stratum can be calculated, respectively. Furthermore, the corresponding relationship between the permeability coefficient and the detected location can be obtained. In view of the abovementioned reasons, the leaking point, the specific position, and the leakage quantity of the detected section could be found out accurately, which will improve the accuracy of the testing results obviously.


2018 ◽  
Vol 246 ◽  
pp. 01030
Author(s):  
Tongtong Wang ◽  
Hao Chen

To comply with the national strategic layout adjustment in recent years, and to promote ecological civilization construction in China western region, it is necessary to study the opportunities and challenges in the Western Route Water Transfer demonstration brought by in ecological and environmental changes in both water-source regions and water receiving regions. By referring to the operation management experience of the Eastern and Middle routes of the South-to-North Water Transfer Project, this paper analyzed the ecological and environmental changes of the Western Route Project’s water transfer rivers, and the relationship between water and sediment of the Yellow River in water-receiving regions, found out the integrating point between the Western Route Project and the new development ideas, and finally concluded that the ecology must be given to priority in the demonstration of the Western Route Project. The early stage work of the Western Route Project needed to follow the general principles as for any major water conservancy project, which includes to demonstrate the project necessity given fully employing the water-saving potential, and to give highest priority to ecological security. Several relationships need be coordinated between: water source regions and water-receiving regions in water-saving, water ecological restoration and water resources development, water pollution control and water resources management, government leading and society participation, etc. These instruments above will guarantee both the water-source and water-receiving regions could benefit from the Western Route Project, help to solve the contradiction between ecological protection and water resources allocation, and facilitate achieving the target of sustainable development.


2011 ◽  
Vol 137 ◽  
pp. 198-204
Author(s):  
Zong Kun Li ◽  
Yu Rong Huang ◽  
Jian You Wang ◽  
Qiang Zi

In order to simulate the seepage field with drain pipes, the air element method is used in this paper. In this method, the pipe elements are regarded as a kind of material with high permeability coefficient and an equivalent hydraulic conductivity is assigned to them. Thus these pipe elements can be included in the conventional seepage calculation as other common elements. Moreover, the difficulty of giving water head boundary to the inner surface of pipes directly is avoided. According to the seepage calculation of the channel with large number of drain pipes in Huangyou part of the middle line in South-to-North water transfer project, the results show that, with drainage-piping, the pore water pressure in channel foundation is reduced significantly.


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