Strengthening Optimization of RC Columns with Rectangular Section by FRP Wrapping

Document Type : Research Article


1 Islamic Azad University KhomeiniShahr Branch

2 Islamic Azad Univiersity, Khomeinishahr branch


Wrapping reinforced concrete (RC) column with FRP sheets improves compressive strength of concrete. Since stress-strain curve of concrete confined with FRP is different from stress[1]strain curve of normal concrete, equations presented by codes for design and analysis of normal (unstrengthened) RC column and based on stress-strain curve of normal concrete cannot be used for design and analysis of columns strengthen with FRP. In this research, first by using stress-strain curve of confined concrete presented by researchers and ACI code, an algorithm was designed to determine axial and flexural capacity of strengthened column and implemented in Visual C# environment. Verification of this work was investigated and confirmed by comparing it with experimental results. The programming was developed in a way that it could be used to optimize the design. Thus, by specifying required information including cross sectional dimensions, number and diameter of rebars, applied axial load and bending moment on column, FRP sheet properties and price, the performed programming can determine which type of FRP, if used, while providing the required flexural and axial capacity , has also the minimum price.


Main Subjects

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