Title:
Shear Design Considering Interaction between Steel Stirrups and Carbon Fiber-Reinforced Polymer Strips
Author(s):
Yungon Kim, Wassim M. Ghannoum, and James O. Jirsa
Publication:
Structural Journal
Volume:
114
Issue:
4
Appears on pages(s):
803-813
Keywords:
carbon fiber-reinforced polymer (CFRP); interaction of steel and CFRP; modification factors; shear design; strengthening
DOI:
10.14359/51689867
Date:
7/1/2017
Abstract:
Conventional shear-strength relations provide conservative estimates for the design strength of new members. However, when members are strengthened with carbon fiber-reinforced polymer (CFRP) vertical strips, the traditional approach of independently summing the concrete, steel, and CFRP contributions to shear strength was found to overestimate the strength increase due to the CFRP material. Thus, modification factors ksF and kfS are proposed to modify the shear-strength equations in ACI 440.2R and account for the interaction between steel and CFRP transverse reinforcement. The proposed factors provide more accurate and less conservative estimates of shear strength of concrete beams, with improved estimates of the strength increase when CFRP materials are added.
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