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EEMS2015 organizing committee
Published in Yeping Wang, Jianhua Zhao, Advances in Energy, Environment and Materials Science, 2018
As a trenchless technology, pipe jacking method has been widely used in underground engineer- ing construction because of its unique technical advantages. Moreover, pipe jacking which requires no excavation formation surface is possible to cross the existing buildings, such as roads, railways, riv- ers, ground, etc. It has small disturbance to the surrounding environment, which saves space com- pared to the open-cut construction method and has a certain economy compared to the shield in the same construction conditions (Ren, 2004). However, there is an important problem about pipe jacking that is how to effectively control surface subsidence caused by construction (Qiao, 2000). This paper firstly discusses the surface deforma- tion of the mechanism and influencing factors, then the practical engineering of the surface defor- mation has been analyzed.
Planning and Construction of Pipelines
Published in Henry Liu, Pipeline Engineering, 2017
Microtunneling is the high-tech version of the horizontal earth-boring system, invented and first used in Japan in the 1970s. The system uses a laser-guided and remote-controlled pipe jacking system, and it permits accurate monitoring and control of the horizontal direction and the grade of the pipe. Because no human entry into the pipe or tunnel is needed, the technology is applicable to small as well as large pipes. This technology is used most often for installing pipes of less than 1-m diameter. The system is rather versatile. It is applicable to all types of soil, and a large variety of depths (up to about 50 m below ground), either above or below groundwater table. The method is best suited for installing sewer pipes, which normally require accurate grade and alignment. One of two methods is used to remove the cut materials (spoil) from the pipe. The first method uses an auger – the same as for the HAB system discussed previously. The second method involves using slurry to mix with the spoil for hydraulic removal by pipes. The slurry also facilitates cutting, and creates enough pressure in front of the machine to prevent or reduce infiltration of groundwater into the borehole.
Trenchless installation technologies of sea outfalls, intakes and landfalls
Published in Cezary Madryas, Andrzej Kolonko, Beata Nienartowicz, Arkadiusz Szot, Underground Infrastructure of Urban Areas 3, 2014
Cezary Madryas, Andrzej Kolonko, Beata Nienartowicz, Arkadiusz Szot
During the pipe jacking process the whole pipeline is pushed through the ground. Rising friction forces between the surrounding ground and the pipe string lead to increasing jacking forces. However the maximum jacking force is strictly limited by the maximum permissible pipe load. To reduce friction, the pipeline should be lubricated continuously. Bentonite suspensions act as lubricants during the pipe jacking process. They are mixed in bentonite plants at the job site and are pumped into the tunnel via hoses or pipes. Through injection nozzles within the jacking pipes, the lubricant is squeezed into the annular gap between the pipeline and the surrounding ground. Thus, the jacking forces can be reduced considerably.
Frictional analysis of pipe-slurry-soil interaction and jacking force prediction of rectangular pipe jacking
Published in European Journal of Environmental and Civil Engineering, 2020
Kai Wen, Hideki Shimada, Wei Zeng, Takashi Sasaoka, Deyu Qian
Pipe jacking is a non-destructive technique used for installing pipes under the ground using a tunnel boring machine and hydraulic jacks located inside a jacking pit, which has been widely used in various applications such as sewer tunnels, oil and gas pipelines, comprehensive pipe rack and telecommunication cable installation (Khazaei, Shimada, Kawai, Yotsumoto, & Matsui, 2006; Shimada, Khazaei, & Matsui, 2004). As the shield advances forward, excavating the earth in its path, sections of pipe are jacked into specified place directly behind it using powerful hydraulic jacks. Normally, circular section of pipes are the most common type utilised in pipe jacking engineering (Chapman & Ichioka, 1999; Sofianos, Loukas, & Chantzakos, 2004; Zhou, Wang, & Huang, 2009). However, compared with the circular cross section, the rectangular pipe has about 20% effective usable area larger than that of circular pipe with the same cross-sectional area, especially when used as underground passage and connective channel between subway stations, which is more practical and economic. Therefore, nowadays, rectangular pipe jacking is becoming more and more popular and gradually applied in underground pipeline engineering (Shimada et al., 2004; Zhiyong, 2011).
Theoretical prediction models for ground settlement during box jacking
Published in Mechanics of Advanced Materials and Structures, 2022
Xiaoqi Zhou, Peixin Shi, Xiangyang Xu, Wei Liu
Pipe jacking is a highly mechanized construction method with the advantages of low construction cost and small disturbance on surrounding environment. It first came into application in German in 1935 and was introduced into China in 1954. At the early stage, pipe jacking was mainly applied in the construction of small circular tunnels for water, electricity and gas supply, or short box tunnels undercrossing roadway or railway due to the limitation of the capacity of jacking machines. Recently, with the advancement of jacking machines and techniques, pipe jacking enjoyed more widespread use in the construction of tunnels with long alignment length and complex cross-section forms.