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Slab Construction Load Distribution in a Multistory-shored RC Structure System with Different Slab Thickness

슬래브 두께가 다른 다층지지 RC 구조 시스템에서의 슬래브 시공 하중 분포

  • 한상민 (광운대학교 건축공학과) ;
  • 김재요 (광운대학교 건축공학과)
  • Received : 2024.01.17
  • Accepted : 2024.02.13
  • Published : 2024.04.30

Abstract

In recent times, accidents involving structural elements, formwork, and shore have been persistently occurring during concrete pouring, especially in multi-story reinforced concrete (RC) structures. In previous studies, research on construction load analysis was mainly conducted for cases where the thickness of all slabs is constant. However, when the thickness of some slabs is different, the variation in the stiffness of slab cross-sections can lead to different distributions of construction loads, necessitating further investigation. In this study, the slab thickness was set as a variable, and the analysis of the distribution of construction loads was conducted, taking into account the influence of changes in slab thickness on the concrete stiffness and structure. It was confirmed that not only the concrete material stiffness but also the slab cross-section stiffness should be considered in the estimation of construction loads when the slab thickness changes. As the slab thickness increases, the maximum construction load and maximum damage parameter on the layer with increased thickness significantly increase, and it was observed that a thicker slab results in a higher proportion of construction load.

최근 콘크리트 타설 중 구조체, 거푸집 및 동바리 사고가 계속해서 발생하고 있으며, 특히 슬래브 두께가 증가하는 다층지지 RC 구조에서 붕괴 사고가 빈번하게 발생하였다. 이전 연구에서는 모든 슬래브 두께가 일정한 경우에 대한 연구가 주로 수행되었으나 일부 슬래브의 두께가 다른 경우, 슬래브 단면 강성의 변화로 전체 슬래브 강성 비율이 달라져 시공 하중의 분포가 달라질 수 있어 이에 대한 연구가 요구된다. 이 연구에서는 슬래브 두께를 변수로 설정하여 슬래브 두께 변화가 콘크리트 강성과 구조물에 미치는 영향을 고려하여 시공 하중의 분포를 분석하였으며, 슬래브 두께가 변화하는 경우 콘크리트 재료 강성 뿐만이 아닌 슬래브 단면 강성도 시공 하중 산정에 고려되어야 함을 확인하였다. 슬래브 두께가 증가 할 경우 두께가 증가하는 층에 작용하는 최대 시공 하중과 최대 손상 변수는 크게 증가하였으며 두께 증가가 클수록 더욱 높은 비율의 시공 하중이 작용함을 확인하였다.

Keywords

Acknowledgement

본 연구는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원(NRF-2022R1F1A1074540)과 2022년도 광운대학교 우수연구자 지원사업에 의해 수행된 연구임.

References

  1. ACI Committee 347 (2005), Guide for Shoring/Reshoring of Concrete Multi-story Buildings (ACI 347.2R-05), American Concrete Institute, ACI, Farmington Hills, MI, 3-7.
  2. Carderon, P. A., Alvarado, Y. A., and Adam, J. M. (2011), A New Simplified Procedure to Estimate Loads on Slabs and Shoring during the Construction of Multistorey Buildings, Engineering Structures, 33(5), 1565-1575.
  3. Chun, S. C., Tak, S. Y., Lee, S. H., Sho, K. H., and Ha, T. H. (2014), Evaluation of Construction Loads of Slabs and Shores with Removing Shores and Placing Reshores, Journal of the Korea Concrete Institute, KCI, 26(3), 385-392 (in Korean, with English abstract).
  4. Hwang, H. J., Hong, G. H., Park, H. G., Kim, Y. N., and Kim, J. Y. (2010), Effects of Shore Stiffness and Concrete Cracking on Slab Construction Load I: Theory, Journal of the Korea Concrete Institute, KCI, 22(1), 41-50 (in Korean, with English abstract). https://doi.org/10.4334/JKCI.2010.22.1.041
  5. Kim, J. Y., and Park, S. B. (2017), Analysis of Effects of Reshoring Works on Short and Long Term Deflections of Flat Plates, Journal of the Korea Institute for Structural Maintenance and Inspection, KSMI, 21(1), 40-48 (in Korean, with English abstract).
  6. Alvarado, Y. A., Calderon, P. A., Gasch, I., and Adam, J. M. (2010), A Numerical Study into the Evolution of Loads on Shores and Slabs during Construction of Multistory Buildings, Comparison of Partial Striking with Other Techniques, Engineering Structures, 32, 3093-3102. https://doi.org/10.1016/j.engstruct.2010.05.028
  7. Grundy, P., and Kabaila, A. (1963), Construction Loads on Slab with Shored formwork in Multistory Buildings, ACI Journal, 60(12), 1729-1738.
  8. KSCS (2021), Concrete Structure Analysis and Design Principles (KDS 14 20 10), 6-7 (in Korean).
  9. Puente, I., Azkune, M., and Insausti, A. (2007), Shore-Slab Interaction in Multistory Reinforced Concrete Buildings during Construction: An Experimental Approach, Engineering Structures, 29(5), 731-741. https://doi.org/10.1016/j.engstruct.2006.06.018
  10. Kim, J. Y. (2009), Applications of Practical Analysis Scheme for Evaluating Effects of Over-Loads during Construction on Deflections of Flat Plate System, Journal of the Computational Structural Engineering Institute of Korea, COSEIK, 22(1), 25-34 (in Korean, with English abstract).