Strengthening and Repairing of the Circular Reinforced Concrete Columns Under Tensile Axial Load Using CFRP Sheet
DOI:
https://doi.org/10.29284/kt8dr616Keywords:
Circular Reinforced Concrete Columns; CFRP Sheets; Tensile Axial Load, Strengthening, Repairing.Abstract
This study examines strengthening and repairing of circular reinforced concrete columns exposed to axial tensile loads using CFRP sheets. The investigational program entails the casting and testing of eight specimens utilizing standard reinforced concrete throughout three phases as follows: Phase I: Control column specimens without preloading and without CFRP reinforcement; Phase II: Column specimens without preloading but with CFRP reinforcement; Phase III: Strengthened preloaded column specimens, which consist of columns reinforced with CFRP after being preloaded to 70% of the maximum load of the control column specimen. The selected primary parameters encompass the type of transverse reinforcement (tie or spiral), the influence of pre-damage, and the configuration of wrapping (completely or double helical). The experimental results demonstrate that changing the transverse reinforcement type from tie to spiral significantly affected the maximum load, resulting in a decrease of roughly 4.8% for the un-strengthened column and about 2.8% for the strengthened column. The column that has undergone pre-damage will possess a reduced load-carrying capacity compared to an undamaged column of equal specifications. Exposing the column to prior damage by loading it to 70% of the maximum load of the control column caused in a decrease of load carrying capacity by 10.8% and 10.77% for the tie and spiral reinforcement cases, respectively, in comparison to the analogous undamaged column. The pre-damaged specimen exhibits reduced initial stiffness compared to the other specimen due to the presence of pre-existing cracks.
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This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
