Title:
Tension Stiffening in RC Beams Retrofitted with NSM CFRP Strips
Author(s):
Publication:
Symposium Paper
Volume:
364
Issue:
Appears on pages(s):
166-176
Keywords:
carbon fiber reinforced polymer (CFRP); rehabilitation; steel corrosion; tension stiffening
DOI:
10.14359/51745463
Date:
12/1/2024
Abstract:
This theoretical study discusses the serviceability of reinforced concrete beams retrofitted with near-surface-mounted (NSM) carbon fiber reinforced polymer (CFRP) strips. Particularly, the research aims to understand the tension stiffening of the strengthened beams under varying degrees of steel corrosion. Five beams are modeled and analyzed, which represent different levels of deterioration up to 100 years. The effects of tension stiffening are evaluated at service and yield loads. Results show that the tension stiffening of the beams decreases as the cross-sectional area of the steel reinforcement reduces. Likewise, the yield and ultimate capacities of the beams diminish with the reduced steel reinforcement. The effective moment of inertia formula stipulated in ACI 318-19 appears to be applicable to the NSM CFRP-retrofitted beams.
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