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Research Article

A Study on the Optimal Pre-loading Calculation of Strut of Retaining Wall through Numerical Interpretation

수치해석을 통한 흙막이벽체 버팀보의 최적 선행하중 산정에 관한 연구

In Jong Moon1
,
Seung Ju Jang2
,
Kang Il Lee3*
문 인종1
,
장 승주2
,
이 강일3*
1Member, Ph.D. Candidate, Dept. of Civil Engineering, Daejin University, 1007 Hoguk-ro, Pocheon-si, Gyeonggi-do 11159, Republic of Korea
2Member, Part Leader, Civil Eng. Office 1, Seoul Metro, 5 Hyoryeong-ro, Seocho-gu, Seoul-si 06693, Republic of Korea
3Member, Professor, Dept. of Civil Engineering, Daejin University, 1007 Hoguk-ro, Pocheon-si, Gyeonggi-do 11159, Republic of Korea
*Corresponding Author
30 June 2021. pp. 45-56
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Abstract

As the utilization of the underground space is activated, deep excavation of ground has been conducted for the installation of underground structures, the earth retaining wall has widely used to minimize deformation of the excavated ground. In particular, as deep excavation is actively progressing in an urban area where structures are concentrated, methods to minimize the deformation of wall have been devised to prevent damage to the structure adjacent to the wall, and one of these methods is the pre-loading method. This method is a method of suppressing the deformation of wall by actively applying a load on the strut to be installed in wall, and research on this method has been conducted recently. However, although related studies have been actively conducted, the management standard for the pre-loading of bracing has not been clearly presented until now. In addition, since the working force in the strut may increase depending on the depth of excavation or the soil condition of the backfill, the magnitude of the pre-loading that can be applied to the brace may decrease. Nevertheless, the magnitude of the pre-loading (more than 50% of the working load) proposed by the previous research results has been uniformly applied to the strut. In this study, 3D finite element analysis was performed to evaluate the application range of the pre-loading of H-beam strut according to the soil conditions of backfill. As a result of the analysis, it was found that there is a very high possibility that a problem may occur in the stability of the structure of strut due to the earth pressure and the pre-loading when the soil condition is weak and deep excavation proceeds. And it was found that the application range of the pre-loading was 5%∼70% of the working load in strut.

Keywords
Pre-loading of bracing
Earth retaining wall
H-beam
3D-FEM

지하공간의 활용이 활성화됨에 따라 지중구조물의 설치를 위해 깊은 굴착이 이루어지고 있으며, 굴착지반의 변형을 최소화하기 위해 흙막이벽체가 많이 활용되고 있다. 특히 도심지에서의 깊은 굴착이 진행함에 따라 벽체에 인접한 구조물의 피해가 발생하지 않도록 벽체 변형을 최소화하기 위한 방법들이 강구되어 왔으며, 이들 방법 중 하나가 버팀 선행하중 공법이다. 이 공법은 벽체의 버팀에 주동적으로 하중을 가해 벽체 변형을 억제하는 방법으로, 최근까지 이 공법에 관한 연구가 진행되어 왔다. 그러나 관련된 연구가 활발히 진행되었음에도 불구하고, 현재까지 선행하중에 대한 명확한 관리기준이 마련되어 있지 않다. 또한 굴착 깊이가 깊거나 배면지반의 상태에 따라 버팀의 작용력이 증가할 수 있으므로, 버팀에 가할 수 있는 선행하중의 크기가 감소할 수 있다. 그럼에도 불구하고 기존 연구결과에서 제안하고 있는 선행하중의 크기(작용하중의 50%이상)를 버팀에 일률적으로 적용하고 있다. 본 연구에서는 벽체의 배면지반조건에 따른 H-빔 버팀보의 선행하중 적용범위를 평가하고자 3차원 유한요소해석을 수행하였다. 해석결과, 연약한 지반조건이고 깊은 심도 굴착이 진행하는 경우 토압과 선행하중에 의한 버팀구조의 안정성에 문제가 발생할 가능성이 매우 큰 것으로 나타났다. 그리고 선행하중의 적용범위는 버팀 작용하중의 5%∼70%인 것으로 나타났다.

References
1
Baek, S. H. (2002), A Behavior of Braced Wall And Adjacent Ground with the Preloading and Wall Stiffness, Master's Degree. Thesis, Graduate School of Ajou University, Ajou University, Korea.
2
Bowles, J. E. (1997), Foundation Analysis and Design, McGraw-Hill, pp.315-316.
3
Canadian Geotechical Society (1992), Foundation Engineering Manual-3rd edition, Canadian Geotechical Society, pp.416.
4
Choi, I. G. and Park, Y. M. (2006), Geotechnical Engineering for field practice, Goomibook, Korea, pp.305-384.
5
Clough G. W. and O'Rourke, T. D. (1990), Construction induced movements of insitu walls, Design and Performance of Earth Retaining Structures, Geotechnical special publication, No.25, ASCE, pp.439-470.
6
Hong, W. P., Yun, J. M., Yea, G. G. and Cho, Y. S. (1997), “A Study on the Behavior of Earth Retaining Walls for Braced Excavation”, Journal of Chungang Universary, Vol.27, No.1997, pp.49-61.
7
Hsai and Yang, F. (1991), Foundation Engineering Handbook-2nd edition, VNR, p.466.
8
Hsieh, P. G. and Ou, C. Y. (1998), “Shape of Ground Surface Settlement Profiles Caused by Excavation”, Canadian Geotechnical Journal, Vol.35, No.6, pp.1004-1017. 10.1139/t98-056
9
Hunt, R. E. (1986), Geotechnical Engineering Analysis & Evaluation, McGraw-Hill, pp.586-587.
10
Hwang, T. H. and Lee, K. I. (2017), “Behavior of Cable Tunnel and Braced Cut Wall by Space of Wall in Numerical Analysis”, Journal of Korean Hazard Mitigation Society, Vol.17, No.5, pp.251-260. 10.9798/KOSHAM.2017.17.5.251
11
Jang, S. W. (2001), Comparative study on the retaining wall's behavior using field measurement data, Master's degree. Thesis, Graduate School of Chonnam University.
12
Ju, S. H. (2013), A Study on the Stability of Excavation Sites Braced by Struts, Master's degree. Thesis, Graduate School of Chungang University.
13
Jung, H. S. (2009), Analysis of Horizontal Displacement Characteristics for Adjacent Ground due to Earth Retaining Walls, Master's degree. Thesis, Graduate School of Hanbat University.
14
KGS (2006), Excavation and Earth Supported Structures, Goomibook, Korea, pp.301-344.
15
Kim, I. and Lee, S. D. (2007), “Behavior of Tunnel Due to Adjacent Gmund Excavation with Pre-Loading on Braced Wall”, Journal of the Korean Geotechnical Society, Vol.23, No.10, pp.163-174.
16
Kung, G. T. C., Hsiao, E. C. L. and Juang, C. H. (2007), “Simplified Model for Wall Deflection and Ground Surface Settlement Caused by Braced Excavation in Clays”, Journal of Geotechnical and Geoenvironmental Engineering, ACCE, Vol.133, No.6, pp.731-747. 10.1061/(ASCE)1090-0241(2007)133:6(731)
17
Lee, C. H., Lee, J. H., Lee, C. K. and Chun, B. S. (2012), “An Numerical Analysis of the Preloading Effect of IPS Retaining Wall through Earth Horizontal Displacement Measuring”, Journal of the Korean Geo-Environmental Society, Vol.13, No.5, pp.25-33.
18
Lee, J. M. (2018), “Behavior of the Ground under a Building due to Adjacent Ground Excavation”, Journal of The Korean Geotechnical Society, Vol.34, No.4, pp.49-55.
19
Mana, A. I. and Clough, G. H. (1981), “Prediction of movement for braced cuts in clay”, J. Geotech. Engrg. Div., ASCE, Vol.107, No.6, pp.759-778. 10.1061/AJGEB6.0001150
20
MIDAS (2010), Manuals of MIDAS GTS: Application Method and Input Material Properties of Interface Element, MIDAS IT.
21
MOLIT (2020), Standard Manual on Underground Safety Impact Assessment, Ministry of Land, Infrastructure and Transport, Korea, pp.131-186.
22
O'Rourke, T. D. (1981), “Ground Movements Caused by Braced Excavation”, Journal Geotechnical Engineering Division, ASCE, Vol.107, No.GT9, pp.1159-1178. 10.1061/AJGEB6.0001183
23
Puller, M. (1996), Deep excavations a practical manual, Thomas Telford, pp.408-409.
24
Shin, J. H. (2015), Geomechanics & Engineering: Analysis and Design, CIR, pp.571-608. 10.1201/b18031-6
25
Sim, J. U., Jeong, S. S. and Lee, J. H. (2015), “Numerical Analysis of Self-Supported Earth Retaining Wall Stabilizing Piles”, Journal of Korean Geotechnical Society, Vol.31, No.5, pp.35-46. 10.7843/kgs.2015.31.5.35
26
USDA (2010), Wood Handbook - Wood as an Engineering Material, USDA, pp.5.1-5.46
27
Yang, K. S. and Oh, S. N. (2000), “Correlation between Strut Preloading and Earth Retaining Structures in Deep Excavations”, Journal of the Korean Geotechnical Society, Vol.16, No.2, pp.23-30.
Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 20
  • No :2
  • Pages :45-56
  • Received Date : 2021-05-24
  • Revised Date : 2021-06-19
  • Accepted Date : 2021-06-23
  • DOI :https://doi.org/10.12814/jkgss.2021.20.2.045
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