Finite Element Analysis based on the Macroelement Method for the Design of Vacuum Consolidation

Hayoung Kim; Kyu-Sun Kim

doi:10.7843/kgs.2022.38.8.29

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2022 Vol.38, Issue 8 Preview Page Next Page

Finite Element Analysis based on the Macroelement Method for the Design of Vacuum Consolidation 진공압밀공법 설계를 위한 Macro-element법 기반 유한요소해석

31 August 2022. pp. 29-37

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Abstract

A three-dimensional analysis is required to interpret the drainage behavior of an improved ground with vertical drains, and the macroelement method enables efficient interpretation considering the three-dimensional drainage effect of vertical drains under two-dimensional plane strain condition. In this study, a novel finite element analysis program was developed by applying the macroelement method to the vacuum consolidation method used in ground improvement practice. The conventional macroelement method was used to calculate the amount of drainage from the vertical drain by setting the excess porewater pressure in the drainage material to zero; however, the program developed in this study was improved to consider negative excess porewater pressure as an actual vacuum consolidation condition. To verify the performance of the program, because of a comparison with the measurement values at the site where the vacuum consolidation method was applied, results predicted by the program and field measurement data showed similar settlement behavior.

Keywords

Macro-element

Plane strain condition

Vacuum consolidation

연직배수재로 개량된 지반의 배수거동을 해석하기 위해서는 3차원 해석이 필요한데, Macro-element법을 이용하면 2차원 평면변형 조건으로 연직배수재의 3차원 배수효과를 고려한 효과적인 해석이 가능하다. 본 연구에서는 지반개량에서 적용되는 진공압밀공법에 Macro-element법을 적용하여 새로운 유한요소해석 프로그램을 개발하였다. 기존의 Macro-element법은 배수재의 과잉간극수압을 0으로 하여 연직배수량을 산정하였으나, 본 연구에서 개발된 프로그램은 부(-)의 과잉간극수압을 실제 진공압밀 조건과 동일하게 고려할 수 있도록 개선하였다. 프로그램의 성능 검증을 위해 진공압밀공법 적용 현장의 계측치와 비교한 결과, 프로그램으로 예측한 결과와 현장 계측데이터는 동일한 침하거동을 나타내었다.

References

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Barron (1948), Consolidation of Fine-grained Soil by Drain Wells, Trans. ASCE, Vol.113, pp.718-742. 10.1061/TACEAT.0006098

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Han, S.J., Yoo, H.K., Kim, B.I., and Kim, S.S. (2013), Settlement Characteristics of Soft Ground Applying the Suction Drain Method, Journal of the Korean Geotechnical Society, Vol.29, No.3, pp.15-27 (in Korean). 10.7843/kgs.2013.29.3.15

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Sekiguchi, H., Shibata, T., Fujimoto, A., and Yamaguchi, H. (1986), A Macro-element Approach to Analyzing the Plane Strain behavior of Soft Foundation with Vertical Drains, Proceedings of the 31st Symposium of the JGS, pp.111-116 (in Japanese).

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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 : 38
No :8
Pages :29-37
Received Date : 2022-06-20
Revised Date : 2022-07-19
Accepted Date : 2022-07-29
DOI :https://doi.org/10.7843/kgs.2022.38.8.29

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

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