A Modification to ACI 440.1R-06 Equation for Determining the Bond Strength of GFRP Bars Using Reliability Analysis

Document Type : Research Article

Authors

1 Ph.D Student, Department of Civil Engineering, Ferdowsi University, Mashhad, Iran

2 Professor, Department of Civil Engineering, Ferdowsi University, Mashhad, Iran

3 Assistant Professor, Department of Civil Engineering, University of Sistan and Baluchestan, Zahedan, Iran

Abstract

ACI 440.1R-06 Code overestimates the bond strength of lap-spliced FRP reinforced concrete beams. In this code, the effect of transverse reinforcement along the splice length on bond strength is not taken into account. In this paper, ACI 440.1R-06 equation was modified for calculating the bond strength of spliced bars in specimens without transverse reinforcement along the splice length using reliability analysis and experimental results. Then, 13 beam specimens were manufactured and tested for evaluating the effect of transverse reinforcement on bond strength. Experimental results show that the influence of transverse reinforcement depends on surface geometries of FRP bars. In this study, the bond strength produced by transverse reinforcement is formulated as a function of surface geometries of bars. This equation is obtained by means of experimental results and Monte Carlo simulation. The bond strength calculated by the proposed equations correlates well with the experimental results in comparison with the values predicted by the code provisions.

Keywords


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