AXIAL COMPRESSIVE BEHAVIOR OF CFRP-STIRRUP CONFINED ROUNDED RECTANGULAR CONCRETE COLUMNS

Abstract

Abstract: Axial compression tests were carried out on 24 carbon fiber polymer-stirrup confined rectangular concrete columns with chamfering. The test shows that CFRP and stirrups form a dual constraint system for the core concrete, which complements each other. It effectively improves the bearing capacity and deformability of the concrete column in which stirrups ensure the residual bearing capacity and ductility after the fracture of FRP. The axial compression performance of FRP-stirrup rectangular concrete columns with chamfering is closely related to the number of FRP layers and the chamfering radius of specimens. Increasing the chamfering radius can improve the properties of the concrete column significantly. With the same layers of FRP, the bigger the chamfering radius is, the better the performance will be. Besides, increasing the number of FRP layers can effectively improve the bearing capacity and deformation capacity of the confined concrete column with identical chamfering radius. Combined with the test results, the bearing capacity calculation model of CFRP-stirrup confined rectangular concrete columns with chamfering is proposed by considering the effective constraint coefficient of the rectangular concrete column, and on the basis of the ultimate stress calculation model of confined circular concrete columns.

Key words: CFRP, stirrups, confinement, concrete, column, axial compressive behavior

CLC Number:

TB332

XU Yang, WEI Yang, CHENG Xun-yu, DUAN Mao-jun. AXIAL COMPRESSIVE BEHAVIOR OF CFRP-STIRRUP CONFINED ROUNDED RECTANGULAR CONCRETE COLUMNS[J]. Fiber Reinforced Plastics/Composites, 2019, 0(6): 5-11.

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