Title:
Seismic Behavior of Carbon Fiber-Reinforced Polymer- Strengthened Reinforced Concrete Members with Various Anchors
Author(s):
Elias I. Saqan, Hayder A. Rasheed, and Tarek Alkhrdaji
Publication:
Structural Journal
Volume:
117
Issue:
4
Appears on pages(s):
3-14
Keywords:
carbon fiber-reinforced polymer (CFRP) splay anchors; cyclic load; flexural strengthening; full wrapping; hysteresis; seismic behavior
DOI:
10.14359/51723517
Date:
7/1/2020
Abstract:
Due to the lack of sufficient experimental studies, the subject of fiber-reinforced polymer (FRP) anchorage has not been addressed in ACI 440.2R-17 in a quantifiable sense. This study is intended to examine the seismic performance of flexural frame members strengthened with carbon fiber-reinforced polymer (CFRP) and anchored using CFRP wrapping and CFRP splay anchors. Five full-scale reinforced concrete assemblages were tested as a control, strengthened with full wraps, strengthened with two arrangements of splay anchors, and strengthened with a combination of a splay anchor and full wrap. The seismic response is traced cyclically up to 3% drift ratios. Various response parameters were extracted from the hysteresis curves of the specimens, and are presented and discussed in this paper. The dense splay anchor specimen along with the splay anchors plus full-wrap specimen provided adequate confinement/stabilization to the plastic hinge region and yielded the best seismic performance overall. The dense splay anchorage arrangement is suggested to use when access is not available to provide full wrapping at the critical plastic hinge zone.
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