The Structural Characteristics of the Temporary Cofferdam in Accordance with the Shape and Size Obtained from Numerical Analysis

Hyun-Joo Kim; Jin-O Choi; Yun-Ho Gwon

doi:10.7843/kgs.2020.36.1.29

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2020 Vol.36, Issue 1 Preview Page

Research Article

The Structural Characteristics of the Temporary Cofferdam in Accordance with the Shape and Size Obtained from Numerical Analysis 유한요소 해석을 통한 형상 및 크기에 따른 가물막이 특성 검토

31 January 2020. pp. 29-38

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Abstract

최근 환기구, 비상탈출용 수직구, 취수탑 가시설 등 지중 가물막이 또는 차수벽체로 원형 가물막이가 많이 적용되고 있다. 원형단면의 경우 벽체에 작용하는 토압이 원형가물막이 형상에 따라 아칭효과(arching effect)로 인하여 작용토압에 대한 구조체의 부재력이 감소하는 것으로 알려져 있다. 본 연구에서는 원형 가물막이에 대한 2D 유한요소해석(FEM)을 활용하여 원형띠장(ring beam) 강성을 산출 후 탄소성해석에 적용하여 부재의 단면력을 검토하였다. 더불어 3D 유한요소해석(FEM)을 통하여 원형단면의 가물막이가 다각형 형태의 가물막이보다 전단력, 휨모멘트, 그리고 발생변위가 최소값을 갖는 것으로 나타났으며, 이로써 원형단면 가물막이가 구조적으로 보다 효율적인 단면 형태임을 확인하였다.

These days the circular cross section cofferdam has been frequently used for the earth retaining structures or cut off wall such as ventilating opening, intake tower in cofferdam, shaft for emergency. By the arching effect, the circular cross section type cofferdam has more advantage than a polygon cofferdam in terms of the structural forces and moment. This paper shows the proper approach to analyze the circular cross section cofferdam using 2D Finite Element Method (FEM) for the circular stiffener (ring beam) evaluation. Besides, the various shapes of cofferdam indluding circular cross section have modeled the 3D Finite Element Mothod (FEM). The circular cross section cofferdam shows the minimum reaction force compared with the other shapes of cofferdam.

Keywords

Arching effect

Circular steel cofferdam

Elasto-plastic analysis

Finite element analysis

Ring beam

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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 : 36
No :1
Pages :29-38
Received Date : 2019-12-03
Revised Date : 2020-01-14
Accepted Date : 2020-01-16
DOI :https://doi.org/10.7843/kgs.2020.36.1.29

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

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