Computers and Concrete

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Application of shrinkage prediction models to restraint crack formation in unbonded post-tensioned slabs

  • Gabriela R. Martínez Lara (Department of Architecture and Architectural Engineering & Institute of Engineering Research, Seoul National University) ;
  • Myoungsu Shin (School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST)) ;
  • Yong-Hoon Byun (School of Agricultural Civil & Bio-Industrial Engineering, Kyungpook National University) ;
  • Goangseup Zi (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Thomas H.-K. Kang (Department of Architecture and Architectural Engineering & Institute of Engineering Research, Seoul National University)
  • Received : 2023.09.23
  • Accepted : 2024.01.21
  • Published : 2024.04.25
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Abstract

This study aims to investigate the effect of restraint configuration on crack formation due to shrinkage-and-creep-induced volumetric change in unbonded post-tensioned slabs. The first part of this study focuses on the comparison of existing shrinkage and creep calculation models that are used to predict the volume-changing behavior of concrete. The second part of this study presents the finite element analysis of a series of architectural configuration prototypes subjected to shrinkage and creep, which comprise unbonded post-tensioned slabs with various restraint configurations. The shrinkage and creep effects were simulated in the analysis by imposing strains obtained from one selected calculation model. The results suggest that a slab up to 300 ft. (90 m) in length does not require a closure strip if it is unrestrained by perimeter walls, and that the most effective restraint crack mitigation strategy for a slab restrained by perimeter walls is a partial wall release.

Keywords

Acknowledgement

The work presented in this paper was sponsored by the National Research Foundation of Korea (NRF) grants (Grant No. 2021R1A5A1032433), and by the Institute of Construction and Environmental Engineering at Seoul National University.

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