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Research Article

A Study on the Load Sharing Ratio and the Settlement of Prebored Open-Ended Steel Pipe Piles

매입 개단 강관말뚝의 하중분담률과 침하량 분석 연구

Chea min Kim1
,
Ki hwan Kim2
,
Do kyun Yoon3
,
Youngkyu Choi4*
김 채민1
,
김 기환2
,
윤 도균3
,
최 용규4*
1Member, Instructor, Dept of Civil Engineering, Kyungsung Univ., 309 Suyeong-ro, Nam-gu, Busan 48434, Republic of Korea
2Member, Senior Staff, Seum tech, 111, Hyoyeol-ro, Buk-gu, Busan 46508, Republic of Korea
3Member, Doctor’s Student, Dept of Civil, Enviornmental, Urban Engineering, Kyungsung Univ., 309 Suyeong-ro, Nam-gu, Busan 48434, Republic of Korea
4Member, Professor, Dept of Civil Engineering, Kyungsung Univ., 309 Suyeong-ro, Nam-gu, Busan 48434, Republic of Korea
*Corresponding Author
30 March 2023. pp. 39-51
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Abstract

The bearing capacity of the prebored pile has been studied by many researchers. However, comparative studies between design data and pile load test data on the load sharing ratio and the settlement were insignificant. Therefore, the design data and the static load test results were compared for the prebored open-end steel piles. In the compressive static pile load test, the load sharing ratios of the base resistance and the shaft resistance were 13%~40% and 60%~87%, respectively and the settlements were measured 2.2mm~4.7mm. In the current bearing capacity calculation formula, the base resistance was shared between 54% and 75%, and the shaft resistance was shared between 25% and 46% and the settlements were calculated about 19.8mm~23.6mm. The settlement in the current bearing capacity calculation formula was 321% to 776% (average : 445%) larger than the settlement in the result of load test. When the settlement were calculated using the load sharing ratio in the pile load tests, it was 137% to 525% larger than the test settlement, and it was as large as 204% on average. It was confirmed that an appropriate evaluation of the load sharing ratio had an important effect on the calculation of pile settlement.

Keywords
Prebored open-ended steel pipe piles
Compressive static pile load test data
The calculated bearing capacity
Measured bearing capacity
Design load level
Load sharing ratio, Settlement

매입말뚝의 지지력은 많은 연구자들에 의해 연구되었다. 하지만 하중분담률과 침하량에 대하여 설계 자료와 말뚝재하시험 지료를 비교한 연구는 미미하였다. 그래서 매입 개단 강관말뚝에 대하여 설계식 자료와 정재하시험 결과를 비교하였다. 압축재하시험에서는 선단지지하중과 주면마찰하중의 분담률이 각각 13%~40%, 60%~87%로 나타났고, 이때의 침하량은 2.2mm~4.7mm로 측정되었다. 현행 지지력 산정식에서는 선단지지력과 주면마찰력이 각각 54%~75%, 25%~46%를 분담하는 것으로 나타났고, 침하량은 19.8mm~23.6mm로 계산되었다. 현행지지력 산정식에서의 침하량은 시험에서의 침하량보다 321%~776% 만큼 크게 나타났으며, 평균적으로 445%만큼 크게 나타났다. 말뚝재하시험에서의 하중분담률을 이용하여 침하량을 산정하면, 시험 침하량보다 137%~525% 만큼 크게 나타났으며, 평균적으로 204% 만큼 크게 나타났다. 하중분담률의 적절한 평가는 말뚝 기초의 침하량 산정에 중요한 영향을 미치는 것으로 확인되었다.

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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 : 22
  • No :1
  • Pages :39-51
  • Received Date : 2022-12-16
  • Revised Date : 2023-02-27
  • Accepted Date : 2023-03-20
  • DOI :https://doi.org/10.12814/jkgss.2023.22.1.039
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