Advances in Computational Design

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Computer-based design optimization of post-tensioned anchor for single-strand

  • Cho, Ah Sir (Department of Architecture, Dongyang Mirae University) ;
  • Kang, Thomas H.K. (Department of Architecture & Architectural Engineering and Engineering Research Institute, Seoul National University)
  • Received : 2021.09.17
  • Accepted : 2021.10.20
  • Published : 2021.10.25
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Abstract

In Korea, a 15.2-mm diameter strand is preferred for a post-tensioning (PT) method to reduce the total tendon and anchor number. However, the anchor for the Ø15.2-mm strand is large and sometimes inefficient while the anchor using the Ø12.7 mm single-strand is common in the United States. This study developed a post-tensioned anchor for Ø15.2-mm unbonded single-strand tendons to address the existing trend in domestic PT construction. The shape of the anchor is optimized to minimize the von Mises stress through a finite element analysis by varying the shape of the tubular body, bearing plate, and gussets. In addition, the design is also determined in consideration of a jacking device, accessories, and workability. ACI 423.7-14, on the other hand, requires the use of an encapsulation system, which is highly resistant to corrosion, for elevated floors. Therefore, the encapsulated anchor was also developed to enhance the durability of PT tendons and buildings.

Keywords

Acknowledgement

This work was supported by the Samsung C&T, National Research Foundation of Korea (grant number NRF-2018R1D1A1B06044752), and Institute of Construction and Environmental Engineering at Seoul National University, as well as Dongyang Mirae University.

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