In order to investigate the joint strengthening effect of Concrete Canvas (CC) and Carbon Fiber Reinforced Plastic (CFRP) on the mechanical properties of reinforced concrete square column, we designed axial compression tests on eight groups of sixteen CC+CFRP reinforced columns, and examined the influences of CFRP band constraint, full constraints and the number of CFRP layers on the failure mode, bearing capacity and ductility of CC+CFRP reinforced columns. Results reveal that the mechanical properties of reinforced concrete square columns are remarkably affected by the restraint mode and quantity of CFRP layers under joint strengthening. CFRP band wrapping is superior to full wrapping in terms of improving bearing capacity, and the bearing capacity of column strengthened by two layers of CFRP improves the most. In terms of deformation, CC ameliorates the failure form of the column, and enhances the ductility and deformation capacity of the column. The research results are of referential value to reducing the corrosion of reinforced steel and upgrading the durability of concrete structures.
Key words
reinforced concrete square column /
concrete canvas /
CC+CFRP joint reinforcement /
axial compression /
mechanical properties
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