A Sensitivity Analysis for the Geotechnical Parameters Estimation of a Ground around a Granular Compaction Pile

Yushik Han; Yongkyu Choi

doi:10.7843/kgs.2015.31.12.5

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2015 Vol.31, Issue 12 Next Page

A Sensitivity Analysis for the Geotechnical Parameters Estimation of a Ground around a Granular Compaction Pile 쇄석다짐말뚝 주변지반의 지반정수산정을 위한 민감도 분석

31 December 2015. pp. 5-15

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Abstract

The GCP (Granular Compaction Pile) for the improvement objective of soft ground has been frequently studied. However, these studies were the results deduced on the basis of the numerical analysis and the laboratory model tests, and there was no study method to apply the effects of the bulging failure of a flexible pile. In this study, the sensitivity of the load-settlement curves of the uniform and the tapered GCP dependant on the geotechnical parameters estimated from N value of standard penetration test (SPT) was analyzed. It was estimated reasonably that, in the very soft clay soil (N=3 or less), elastic modulus was 700～2000 kPa and Poisson’s ratio was 0.40～0.48.

Keywords

GCP (Granular Compaction Pile)

Numerical analysis

Geotechnical parameters

Bulging failure

PT (Standard Penetration Test)

The sensitivity

Very soft clay

연약지반 개량목적으로 쇄석다짐말뚝에 대한 연구는 많이 진행되어 왔다. 하지만 이러한 연구들은 수치해석 및 실내모형실험을 토대로 도출해 낸 결과이며, 연성말뚝(기초의 강성이 작아 유연한 기초)의 벌징파괴에 대해 효율적으로 적용할 수 있는 방안에 대한 연구는 없는 실정이다. 이 연구는 SPT 시험의 N치로 추정된 지반물성치의 변화에 따른 쇄석다짐말뚝의 등단면 및 변단면의 하중-침하량 관계에 대한 민감도를 분석하였다. 정재하시험의 하중-침하량 결과에 기초하여 수치해석 시 지반에 대한 지반 물성치를 추정하였다. N치가 3이하인 매우 연약한 점토층의 탄성계수는 700～2000kPa, 푸아송비는 0.40～0.48의 값이 합리적인 것으로 판단되었다.

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 : 31
No :12
Pages :5-15
Received Date : 2015-05-12
Revised Date : 2015-08-04
Accepted Date : 2015-08-27
DOI :https://doi.org/10.7843/kgs.2015.31.12.5

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

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