Study on stability and design guidelines for the combined system of scaffolds and shores

  • Peng, Jui-Lin (Department of Civil and Construction Engineering, National Yunlin University of Science & Technology) ;
  • Wang, Chung-Sheng (Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology) ;
  • Wang, Shu-Hong (School of Resource and Civil Engineering, Northeastern University) ;
  • Chan, Siu-Lai (Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University)
  • Received : 2019.09.05
  • Accepted : 2020.04.11
  • Published : 2020.05.10


Since the scaffold is composed of modular members, the total height of multi-story scaffolds does not often meet with the headroom of construction buildings. At this time, other supporting members need to be set up on the top of scaffolds. However, the mechanical behaviors of the combined system of scaffolds and other supporting members have seldom been discussed. This study explores the stability of the combined system of scaffolds and shores. The loading tests conducted in the laboratory show that the critical load of the combined system of two-story scaffolds and wooden shores is about half that of the three-story scaffold system with the same height. In the failure of both the "scaffold system" and the "combined system of scaffolds and shores' after loading, the deformation mainly occurs in the in-plane direction of the scaffold. The outdoor loading test shows that no failure occurs on any members when the combined system fails. Instead, the whole system buckles and then collapses. In addition, the top formwork of the combined system can achieve the effect of lateral support reinforcement with small lateral support forces in the outdoor loading test. This study proposes the preliminary design guidelines for the scaffolding structural design.


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