Construction Technology Points of Large Diameter Bagged Concrete Bored Pile

RADON enterprises are historically responsible in Russia for institutional waste of low and intermediate activity level. MosNPO RADON is a leading organization for 16 enterprises of RADON system, established in the early 60-s, only 14 from which are now in operation and have about 10% of their repositories available for upcoming waste. Construction of new repositories and selection of new perspective sites is very actual problem for RAW management in Russia now. Traditionally near surface repositories are considered to be acceptable for storage or even disposal of low and intermediate level waste (LILW), which decay to safe level in some hundreds of years. Forty years experience in LILW isolation using near surface repositories at Russian RADON facilities has shown that a lot of operational and natural factors impact on the engineered barriers and may cause failure of the isolation (freezing-thawing cycles, construction works). In addition construction of new old-type repositories requires more area. Since 1997 development and testing of Large Diameter Wells (LDW) as a new type of repositories for low and intermediate level waste is carried out at Zagorsk site. MosNPO RADON specialists developed the LDW construction technology with the aim to use such wells for LILW isolation in moraine clays. The diameter of LDW-type repository may range from 1 to 5 m depending on drilling rig capabilities and performance parameters of host rock. The depth of well (repository) depends on geological parameters and hydro-geological conditions at the site. These features affect on the siting process by additional geological and hydro-geological requirements. In result of preliminary studying of Central Russia two regions were found to be perspective for construction of LDW-type repositories.

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Construction Technology of Composite Cofferdam for Main Pier Bearing Platform of Dongjiang Lichuan Bridge

E3S Web of Conferences ◽

10.1051/e3sconf/202016504047 ◽

2020 ◽

Vol 165 ◽

pp. 04047

Author(s):

Jianping Wang

Keyword(s):

Steel Sheet ◽

Economic Benefits ◽

Construction Technology ◽

High Quality ◽

Rock Stratum ◽

Advantages And Disadvantages ◽

Construction Methods ◽

Bored Pile ◽

Geological Conditions ◽

Pile Cap

Dongjiang Lichuan Bridge in Dongguan City is a curved tower curved beam cable-stayed bridge with a main span of 138m and no back cable. The main pier cap is located on the bank slope of Dongguan Waterway on one side of Nandi Road. The cushion cap is dumbbell type, and the left and right cushion caps are connected by tie beams. In most areas, the top of rock stratum is above the bottom of bearing platform. The rock stratum within the buried depth of bearing platform is moderately to strongly weathered argillaceous siltstone. The geological conditions are complex and the construction is difficult. In line with the principles of speeding up the construction process and improving economic benefits, comprehensive analysis and weighing advantages and disadvantages, the main pier cap adopts a composite cofferdam of filling soil to build an island and combining bored pile rows and steel sheet piles. The construction task of bearing platform of main pier has been completed with high quality. Compared with other cushion cap construction methods, this construction method has the advantages of fast construction, high quality, simple safety, energy saving and environmental protection. This paper briefly introduces the design scheme of composite cofferdam, expounds in detail the operation steps of steel sheet pile construction and the problems needing attention in construction, and provides good reference experience for similar pile cap construction.

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The Application Research and Discussion on a Viaduct Artificial Excavated Pile Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.2449 ◽

2012 ◽

Vol 446-449 ◽

pp. 2449-2452

Author(s):

Dong Guo Li ◽

Gui Mei Shi

Keyword(s):

Bearing Capacity ◽

Pile Foundation ◽

Retaining Wall ◽

Wall Effect ◽

Construction Technology ◽

Application Research ◽

Technical Work ◽

Bored Pile

A viaduct of the Qinglai expressway fourth contract was artificial excavated piles. The construction technical work was regarded as an example. The technical comparison were done between the artificial excavated pile and the bored pile on the pile foundation bearing capacity and the retaining wall effect . The artificial excavated pile replacing the bored pile was feasible, and the construction technology and the key problems of the artificial excavated piles were confirmed. The references were provided to the similar projects.

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