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Research Article

An Experimental Study on Bearing Capacity of Drilled Shaft with Mid-size

중구경 현장타설말뚝의 지지력 특성에 관한 실험적 연구

Kwang-Wu Lee1
,
Seung-Kyong You2
,
Jeong-Jun Park3
,
Jung-Mann Yun4
,
Gigwon Hong5*
이 광우1
,
유 승경2
,
박 정준3
,
윤 중만4
,
홍 기권5*
1Member, Senior Researcher, Department of Infrastructure Safety Research, Korea Institute of Civil engineering and building Technology, 283 Goyangdae-Ro, Ilsanseo-Gu, Goyang-Si, Gyeonggi-Do 10223, Republic of Korea
2Member, Professor, Dept. of Civil Engineering, Myongji College, 134 Gajwa-ro, Seodaemun-gu, Seoul 03656, Republic of Korea
3Member, Principal Researcher, Incheon Disaster Prevention Research Center, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
4Member, Professor, Department of Construction Information System, ShinAnsan University, 135 Shinansandeahak-ro Danwon-gu, Ansan, Republic of Korea
5Member, Director, Institute of Technology Research and Development, Korea Engineering & Construction, 3-16 Jungdae-ro 25-gil, Songpa-gu, Seoul 05661, Republic of Korea
* Corresponding Author
30 December 2019. pp. 263-272
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Abstract

본 연구에서는 중구경 현장타설말뚝의 활성화를 위하여, 말뚝재하시험을 이용한 지지력 특성을 평가하였으며, 그 결과를 설계지지력 예측방법과 비교하였다. 정재하시험 결과, 말뚝의 강도가 높은 경우에 낮은 강도에 비하여 약 2.4배 수준의 허용지지력을 나타내는 것으로 평가되었고, 동재하시험 결과에서는 높은 말뚝 강도의 경우가 낮은 경우보다 약 1.4배∼1.5배 수준의 허용지지력을 나타내는 것으로 분석되었다. 정재하시험과 동재하시험의 허용지지력에 대한 비교 결과, 동일한 침하량 조건에서는 그 차이가 3%∼6% 범위를 나타내었다. 그리고 재하시험 결과와 설계지지력 예측방법을 이용한 지지력 산정결과를 비교한 결과, 선단지지력 및 주면마찰력에 대한 하중분담율에 있어서, FHWA 제안식이 보다 합리적인 예측이 가능한 것으로 확인되었다.

This paper describes the results of bearing capacity using field loading test of pile, in order to extend the applicability of drilled shaft with mid-size, and the results were compared with the prediction results of design bearing capacity by empirical formular. The static load test result showed that the allowable bearing capacity of high pile strength was about 2.4 times higher than that of low pile strength. The dynamic load test result showed that the allowable bearing capacity of high pile strength was about 1.4 times∼1.5 times higher than that of low pile strength. The comparison result of allowable bearing capacity between static and dynamic load test showed that the difference of allowable load ranged from 3% to 6% under the same settlement conditions. As a result of comparing the ultimate bearing capacity by load test and design bearing capacity, it was found that the FHWA proposed equation could be more reasonable than the other proposed equation in load sharing ratios of end bearing and skin friction.

Keywords
Drilled shaft
Field loading test
Bearing capacity
End bearing
Skin friction

References
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Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 18
  • No :4
  • Pages :263-272
  • Received Date : 2019-12-09
  • Revised Date : 2019-12-23
  • Accepted Date : 2019-12-24
  • DOI :https://doi.org/10.12814/jkgss.2019.18.4.263
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