Stress Analysis and Calculation Formular Proposal for Soil-Cement Wall Construction Method with Eccentrically Arranged H-Pile

Hyun-Gi Kim; Hyun-Ik Kim; Beom-Joon Kim

doi:10.7843/kgs.2024.40.6.7

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2024 Vol.40, Issue 6 Next Page

Stress Analysis and Calculation Formular Proposal for Soil-Cement Wall Construction Method with Eccentrically Arranged H-Pile 편심 배치된 심재를 갖는 소일시멘트벽체(ESCW) 공법의 응력 산정식

31 December 2024. pp. 7-19

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Abstract

The soil-cement wall (SCW) construction method, which is an earth retaining wall techniques, involves forming a wall by mixing cement slurry with native soil and inserting steel reinforcements, e.g., H-beams, at regular intervals to create a retaining wall. This method offers several advantages, e.g., reduced construction time, a high degree of stiffness, and the formation of a continuous retaining wall with a uniform diameter. Alongside these advantages, the eccentrically SCW (ESCW) method has been proposed, where reinforcements are inserted at the outermost excavation section to maximize the arch effect and prevent flexural failure. The superiority of the ESCW method has been studied based on the construction methods and calculation formulas. In this study, formulas for the maximum eccentricity, critical angle, and excavation diameter for the stress calculation for ESCW are suggested, and stress calculation formulas for the ESCW method are presented. In addition, a stress comparison and evaluation of the SCW and ESCW methods were conducted based on specific cases. A comparison of the stress under site-specific conditions using the calculation formulas for the SCW method based on the simplified methods and the proposed ESCW method demonstrates that the compressive stress and shear stress of the ESCW method were reduced by an average of 17% and 32%, respectively, compared with the SCW method. A further evaluation of the ESCW and SCW methods was conducted through finite element analysis, showing that the stress in the ESCW method was reduced by approximately 10%-30% compared with that of the SCW method, and the displacement was reduced by approximately 33%-46%, which confirms that the ESCW method is more efficient in resisting soil pressure and ensuring stability. In addition, there is currently no research on establishing or verifying a Korean numerical model for the SCW method; thus, it is deemed necessary for future studies.

Keywords

SCW

ESCW

Eccentrically arranged H-pile

Arching effect

Stress calculation formular

흙막이 공법 중 하나인 Soil-cement wall(SCW) 공법은 시멘트 유액과 지반 토사를 혼합하여 벽체를 형성한 후 일정 간격으로 H형강과 같은 강재를 삽입하여 흙막이 벽체를 형성하는 공법으로, 공기단축, 높은 차수성 및 균일한 직경의 연속된 차수벽 형성의 장점을 가지고 있는 공법이다. 이러한 장점과 함께 굴착 최외단면에 심재가 삽입되어 휨파괴가 발생하지 않고 아치효과를 극대화 할 수 있는 Eccentrically Soil-cement wall(ESCW) 공법이 제안되었으며, 도해법 및 계산식에 따라 우수성이 연구되었다. 본 연구에서는 ESCW공법의 응력 산정에 필요한 최대편심량, 임계각도 및 굴착직경 산정식을 제시하여 응력 산정식을 확립하였고, 특정 사례를 통한 SCW 공법과의 응력 비교검토를 수행하였다. 간편법에 따른 SCW의 산정식과, 제안된 ESCW공법을 통해 특정 사이트 조건에 대한 응력을 비교 검토해본 결과, ESCW공법의 압축응력은 평균 17%, 전단응력은 평균 32%가 SCW보다 감소된 결과를 보였다. ESCW공법을 평가하기 위한 추가적인 방법으로 유한요소해석을 통한 SCW와 ESCW공법의 비교 검토를 수행하였고, 응력 검토 결과 ESCW의 경우가 SCW보다 10~30% 정도 저감된 것으로 평가되었으며, 변위의 경우 33~46% 정도 줄어든 것으로 평가되어 ESCW 공법이 토압 저항성과 안정성에 대해 더 효율적인 것을 확인하였다. 또한 현재로서는 SCW에 대한 한국형 수치모델의 확립이나 검증에 대한 연구가 전무하기 때문에 이에 대한 연구가 후속연구로 수행될 필요가 있는 것으로 사료된다.

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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 :6
Pages :7-19
Received Date : 2024-06-26
Revised Date : 2024-11-11
Accepted Date : 2024-11-11
DOI :https://doi.org/10.7843/kgs.2024.40.6.7

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

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