Title:
Transferring Reaction Forces by External Post-Tensioning of Load-Bearing Shear Walls
Author(s):
Giwan Noh, Thomas H.-K. Kang, Dai-Young Yune, and Tae-Ho Kim
Publication:
Structural Journal
Volume:
121
Issue:
4
Appears on pages(s):
101-114
Keywords:
external post-tensioning; foundation retrofitting; load-transfer; remodeling; vertical expansion.
DOI:
10.14359/51740711
Date:
7/1/2024
Abstract:
Remodeling aging structures is common to enhance their structural,
economic, and functional performance. However, the exceeding of
bearing capacity of existing piles caused by increased upper loads
due to vertical expansion frequently hinders their revitalization. In
this paper, a methodology is proposed to control the demand-tocapacity ratio of existing piles without retrofitting the foundation,
which is often accompanied by technical limitations and safety
issues. A total of 12 tests were performed on four full-scale specimens, with tendon shape, wall thickness, boundary condition, and construction sequence as variables. Factors affecting load-transfer performance were identified based on test results. The target load transfer pattern implemented in accordance with the tendon shape was confirmed. To verify the validity of the method, tests using tendon shape and wall thickness as variables were compared with results from finite element analysis.
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