Field trials of large-diameter multi-belled piling method
Bored piles with an enlarged lower section (called a ‘bell’) have been commonly constructed by the earth drilling method for high-rise building foundations in Japan. Moreover, several multi-belled pile methods with both bottom and intermediate bells have appeared. These offer much higher bearing capacity or uplift resistance for super-tall or long-span buildings. The authors have developed a new multi-belled pile method able to construct piles with enlargements up to 5.5 m in diameter without the use of hydraulic equipment. By shaping the upper tilt of the bell with a maximum angle of 30 degrees, the amount of drilled soil and placed concrete is suppressed. This paper describes the new method and presents the results of field trials with the new equipment aimed at verifying the shape and strength of the resulting piles.
Keywordscast-in-situ pile multi-belled pile construction method field trial high-strength concrete
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- Architectural Institute of Japan (AIJ) (2015). Japanese architectural standard specification for reinforced concrete work. JASS, 5 (in Japanese).Google Scholar
- Japan Foundations Engineering Association (JFEA) (2017). Recommendation for practice of cast-in-situ concrete pile, pp 41–45 (in Japanese).Google Scholar
- Ninomiya, T., Komuro, T., Toyama, J., Horii, Y., Sugimura, M., Somiya, Y., Watanabe, Y., Watanabe, T., Tomita, N., Nishiyama, S., Nakamura, I., and Hoshi, S. (2017). Design of piled raft foundation with diaphragm walls for high-rise building, parts 1-5. Summaries of technical papers of annual meeting AIJ, pp 531–540 (in Japanese).Google Scholar
- Tomlinson, M. J. (1995). Foundation design & construction 6th edition, pp 149–156.Google Scholar
- Watanabe, K., Ishii, Y., Sudo, T., and Wachi, Y. (2013). Nodular cast-in-place concrete pile and nodular diaphragm wall. JGS Journal, 61(1), pp 36–37 (in Japanese).Google Scholar