A Study on the Proposal of Empirical Coefficients for Settlement Estimation of Embedded Piles in Weathered Ground

Seungtyul Oh; Tae-Hyung Kim; Chea min Kim; Kihwan Kim

doi:10.12814/jkgss.2026.25.3.049

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2026 Vol.25, Issue 3 Preview Page Next Page

Research Article

A Study on the Proposal of Empirical Coefficients for Settlement Estimation of Embedded Piles in Weathered Ground 매입말뚝공법의 침하량 산정을 위한 풍화대 지반의 경험계수 제안 연구

30 September 2026. pp. 49-63

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Abstract

As architectural and civil engineering structures continue to increase in scale, pile foundations are required to support increasingly larger structural loads. In Korea, embedded piles using PHC and steel pipe piles are widely used because of their constructability and relatively low environmental impact. The settlement of embedded piles is generally estimated using Vesic's empirical equation. However, the empirical coefficients proposed by Vesic were primarily developed for soil conditions and are also commonly applied to weathered ground. In this study, the results of static pile load tests and load-transfer tests conducted on embedded piles installed in weathered soil and weathered rock were analyzed. The measured settlements were compared with those calculated using Vesic's settlement equation, and the calculated settlements were found to be approximately 3.1 to 7.8 times greater than the measured values. Accordingly, empirical coefficients suitable for weathered ground were back-calculated using the measured settlements and load-sharing ratios between shaft resistance and tip resistance. Based on the analysis, empirical coefficients of 0.042 and 0.033 are proposed for weathered soil and weathered rock, respectively. The proposed coefficients are expected to improve the applicability of Vesic's settlement equation to weathered ground and provide a more rational basis for settlement estimation of embedded piles.

Keywords

Embedded piles

Weathered ground

Static pile load test

Settlement

Empirical coefficient

Load-sharing ratio

최근 건축 및 토목 구조물이 대형화됨에 따라 상부 구조물을 지지하는 말뚝기초에도 큰 하중을 지지할 수 있는 성능이 요구되고 있다. 국내에서는 시공성과 환경적 영향을 고려하여 PHC말뚝 및 강관말뚝을 이용한 매입말뚝공법이 널리 적용되고 있다. 본 연구에서는 풍화토 및 풍화암 지반에 근입된 매입말뚝을 대상으로 수행된 압축정재하시험과 하중전이시험 결과를 분석하고, 실제 시험 침하량과 Vesic의 침하량 산정식으로 계산된 침하량을 비교하였다. 분석 결과, 일반적인 사질토 지반의 경험계수 0.09를 적용하여 계산된 침하량은 시험 침하량보다 약 3.1~7.8배 크게 나타났다. 이에 시험에서 측정된 침하량과 주면마찰력 및 선단지지력의 하중분담율을 이용하여 풍화대 지반에 적합한 경험계수를 역산하였다. 그 결과, 풍화토 지반에서는 0.042, 풍화암 지반에서는 0.033의 경험계수를 제안하였다. 본 연구에서 제안한 경험계수는 풍화대 지반에서 기존 Vesic 경험계수의 적용에 따른 과도한 침하량 산정을 개선하고, 매입말뚝의 침하량을 보다 합리적으로 산정하기 위한 참고값으로 활용될 수 있을 것으로 판단된다.

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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 : 25
No :3
Pages :49-63
Received Date : 2026-05-18
Revised Date : 2026-08-21
Accepted Date : 2026-09-01
DOI :https://doi.org/10.12814/jkgss.2026.25.3.049

Journal of the Korean Geosynthetics Society ISSN:2508-2876(Print) 2287-9528(Online) 한국지반신소재학회 논문집

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