Behavior and Strength of Steel Fiber Reinforced Self-compacting Concrete Columns Wrapped by Carbon Fiber Reinforced Polymers Strips

Document Type : Original Article


1 Civil Engineering Department, University of Technology, Baghdad, Iraq

2 The Ministry of Transport and Communications, Baghdad, Iraq


Strength capacity of reinforced concrete columns is very important to resists and transmit the external loadings. For Architects the engineerings requirements to use small cross section of reinforced concrete columns or in case of poor control quality we need to increase the compressive strength of concrete or use a strengthening technique of the structural elements such as column. In the present paper, the behavior and strength of four steel fiber reinforced self-compact concrete columns reinforced by one layer of CFRP that is wrapped around a square of reinforced concrete columns subjected to static loads is investigated. Self-compacting concrete by using limestone powder is adopted and is mixed with different percentages of steel fiber such as 1%, 1.5% and 2%. Different tests are adopted to investigate the mechanical properties of self-compacted concrete mixed with different steel fiber percentages. Test results show that there is an increase in concrete mechanical properties such as compressive strength, splitting tensile strength and modulus of rupture that reflects on the increase in load capacity of column; specimens when wrapped by CFRP. The increment in columns strength capacity is more than 50% as compared with the control column. All the test specimens are modeled using finite element analysis by ANSYS and the numerical results are compared with tested specimens.


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