Flexural Strengthening of Voided Concrete Slabs with AFRP, CFRP and GFRP

Document Type : Research Paper

Authors

1 Department of civil engineering, ,Guilan University,Rasht,Iran

2 Department of Civil Engineering,Faculty of Engineering,Guilan university,Rasht,Guilan

Abstract

Studies have shown that one of the leading causes of earthquake inflicting irreparable damage has been the high weight of structures. Using FRP composite sheets -due to the proper mechanical and physical properties to reinforce and improve concrete members in load-bearing, removal of concrete in the deflection and increasing the ductility of concrete - is an appropriate option. The purpose of this study is to strengthen voided concrete slabs with AFRP, CFRP and GFRP. In this study, 10 specimens of reinforced concrete with dimensions of 150×70×20 cm were investigated. The results demonstrated that the amount of load capacity in the Network strengthened specimen with CFRP compare to the control sample 175% and, in Linear, strengthened specimen with AFRP in comparison with the control sample 153% increased. This value in comparison with Solid specimens increased by about 96% for samples having been strengthened with CFRP and 91% for those strengthened with AFRP. The maximum displacements have been presented in the specimen strengthened with CFRP (236%) compared to that of the control sample and in the specimen strengthened with GFRP (99%) compared to that of the control sample. The stiffness amounts in Linear specimen strengthened with CFRP 225% compared to that of the control sample and in Network specimen strengthened with AFRP 136% compared to the that of control sample also increased.

Keywords


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