Experimental Analysis of Load Distribution in Pile Foundations Using a Smart Preloading System for Vertical Extension Remodeling

Jinoh Won; Junsung Kim; Hyoungmin Song; Kiho Lee; Sewook Son; Chunwhan Cho

doi:10.7843/kgs.2024.40.5.131

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2024 Vol.40, Issue 5 Preview Page

Experimental Analysis of Load Distribution in Pile Foundations Using a Smart Preloading System for Vertical Extension Remodeling 수직증축 리모델링시 스마트 선재하시스템 적용을 위한 말뚝기초의 하중분담 실험적 연구

31 October 2024. pp. 131-142

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Abstract

To analyze the preloading effects and the load distribution ratio between existing piles and reinforcing piles during vertical extension remodeling, pilot tests were conducted. Previous studies on load distribution typically involved small-scale experiments or numerical simulations. The stiffness of piles used in load distribution designs is often estimated using empirical formulas, which exhibit significant variability. In this study, steel reinforcing piles were installed adjacent to existing PHC piles at an apartment construction site. The actual stiffness of the individual piles was determined through static load tests and compared with empirical formula predictions. The pilot tests (full-scale load-distribution tests), applying column loads simultaneously to the existing and reinforcing piles, demonstrated that column loads are distributed based on the stiffness ratio of each pile. The pilot test outcomes were further compared with long-term measurement data. A smart preloading system was developed in this study to address the preloading loss observed in previous systems, and its applicability was validated through full-scale tests.

Keywords

Remodeling

Pile

Load-distribution

Pile stiffness

Smart preloading system

본 연구에서는 수직증축 리모델링시 선재하 효과를 파악하고 하중분담 효과를 검증하기 위하여 실규모의 현장시험을 수행하였다. 기존 하중분담관련 연구가 주로 실내시험이나 수치해석기법을 통해 이루어졌고 설계에 적용되는 말뚝강성도 경험식으로 산정되어 편차가 커서 실규모 현장시험의 필요성이 절실하다. 이에 본 연구에서는 PHC 말뚝으로 지지되는 아파트 현장에서 말뚝주변에 보강말뚝을 설치하고, 말뚝강성 확인시험을 통해 실제 개별 말뚝강성을 산정하여 경험식과 비교하였다. 기존말뚝과 보강말뚝에 동시에 재하하는 하중분담시험을 통해 실제 말뚝강성비대로 하중분배가 이루어지는 것을 확인하였으며 장기계측결과와 비교하였다. 또한 기존 선재하방법의 가압하중 소실문제 해결을 위해 동시 가압이 가능한 스마트 선재하 시스템을 개발하여 기둥 2개를 동시 가압하여 현장 적용성을 검증하였다.

References

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Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 40
No :5
Pages :131-142
Received Date : 2024-10-24
Revised Date : 2024-10-25
Accepted Date : 2024-10-25
DOI :https://doi.org/10.7843/kgs.2024.40.5.131

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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