Title:
Behavior of Anchored Carbon Fiber-Reinforced Polymer Strips Used for Strengthening Concrete Structures
Author(s):
Wei Sun, James O. Jirsa, and Wassim M. Ghannoum
Publication:
Materials Journal
Volume:
113
Issue:
2
Appears on pages(s):
163-172
Keywords:
anchor(s); bonded; carbon fiber-reinforced polymer; concrete members; strengthening; strip(s); unbonded
DOI:
10.14359/51688637
Date:
3/1/2016
Abstract:
The anchorage of carbon fiber-reinforced polymer (CFRP) strips
using CFRP anchors is gaining acceptance in strengthening applications of concrete members. CFRP anchors can fully develop the strength of CFRP strips when adequately detailed. However, parameters that influence the behavior and strength of CFRP strips and anchors are not well understood. In this study, 26 tests on concrete beams were conducted to study the influence of five key parameters on CFRP anchor effectiveness: 1) the width of the anchored CFRP strip; 2) the material ratio of CFRP anchor to CFRP strip; 3) the concrete strength; 4) the length/angle of anchor fan; and 5) the bond condition between a CFRP strip and concrete. Results indicate that narrow anchored CFRP strips developed higher stresses at fracture than wide strips and required smaller anchor material ratios to be fully developed. Test results provide valuable data for designing anchored CFRP strengthening systems.
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