Interfacial stress analysis of steel beams reinforced with bonded prestressed FRP plate

Fiber-reinforced polymer (FRP) composites are becoming suitable and substantial materials in repairing and replacing conventional metallic materials because of their high strength and stiffness. Steel beams can be strengthened in flexure using bonded FRP or using steel plates. In such plated beams, shear forces develop in the bonded beam and these will be transferred to the FRP plate via the adhesion technique. Thus, the interfacial shear stress and normal stress will develop consequently, and debonding may occur at the FRP plate ends due to high interfacial stress values in this area. This original research aims to study the debonding phenomenon using an analytical and a numerical finite element models, in order to identify the interfacial stresses of a steel beam strengthened by the FRP plate with taper model, taking into account a new coupled approach of prestressing force and hygrothermal effect. This article explores the effects of various parameters, such as geometrical and physical properties, on the stress behavior of FRP composites.

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Interfacial stress analysis of a thin plate bonded to a rigid substrate and subjected to inclined loading

International Journal of Solids and Structures ◽

10.1016/j.ijsolstr.2006.12.028 ◽

2007 ◽

Vol 44 (16) ◽

pp. 5247-5271 ◽

Cited By ~ 22

Author(s):

H. Yuan ◽

J.F. Chen ◽

J.G. Teng ◽

X.Z. Lu

Keyword(s):

Stress Analysis ◽

Thin Plate ◽

Interfacial Stress ◽

Rigid Substrate ◽

Inclined Loading

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Interfacial stress analysis in TSVs by considering the sidewall scallop

2014 Joint IEEE International Symposium on the Applications of Ferroelectric, International Workshop on Acoustic Transduction Materials and Devices & Workshop on Piezoresponse Force Microscopy ◽

10.1109/isaf.2014.6917956 ◽

2014 ◽

Author(s):

Wu Wei ◽

Qin Fei ◽

Li Wei ◽

Shi Ge

Keyword(s):

Stress Analysis ◽

Interfacial Stress

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Interfacial Stress Analysis of Adhesively Bonded Lap Joint

Materials ◽

10.3390/ma12152403 ◽

2019 ◽

Vol 12 (15) ◽

pp. 2403 ◽

Cited By ~ 3

Author(s):

Shiuh-Chuan Her ◽

Cheng-Feng Chan

Keyword(s):

Finite Element ◽

Shear Modulus ◽

Stress Analysis ◽

Analytical Solutions ◽

Interfacial Stress ◽

Bonded Joints ◽

Lap Joint ◽

Adhesively Bonded ◽

Adhesively Bonded Joints ◽

Adhesive Thickness

The use of adhesively bonded joints in place of traditional joining techniques such as bolted or rivet joints is becoming greatly popular in recent years. Interfacial stress in the adhesive is critical to the strength of adhesively bonded joints. It is necessary to predict the interfacial stresses accurately to ensure the safety of joints. In this work, an analytical model is explicitly presented to evaluate the stresses in a double lap joint. The equilibrium equations in the adhesive overlap region are derived on the basis of elasticity theory. The governing equations are presented in terms of shear and peel stresses in the adhesive. Analytical solutions are derived for the shear and peel stresses, which are considered to be the main reason for the failure of the double lap joint. To verify the analytical solutions, the finite element method is conducted using the commercial package ANSYS. Results from the analytical solution agree well with finite element results and numerical investigations available in the literature. The effect of the adhesive thickness, shear modulus, adherend Young’s modulus and bonding length on the shear and peel stresses in the adhesive of the double lap joint are studied. Numerical results demonstrate that both the maximum shear and peel stress occur at both ends of the bonding region. The maximum values of the shear and peel stresses increase as the adhesive thickness decreases and as the adhesive shear modulus increases provided that the adhesive thickness is sufficiently small. The simplicity and capability to obtain analytical expressions of the shear and peel stresses for double lap adhesive bonded joints makes the proposed analytical model applicable for the stress analysis and preliminary structural design.

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Experimental Study on Fatigue Life of Steel Beams Strengthened with a CFRP Plate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.163 ◽

2008 ◽

Vol 33-37 ◽

pp. 163-168 ◽

Cited By ~ 2

Author(s):

Jun Deng ◽

Marcus M.K. Lee ◽

Pei Yan Huang

Keyword(s):

Fatigue Life ◽

Crack Initiation ◽

Crack Propagation ◽

Fatigue Test ◽

Interfacial Stress ◽

Steel Beams ◽

Test Results ◽

Load Range ◽

Cfrp Plate ◽

Crack Initiation Life

The adhesive bonding between the steel beam and carbon fibre reinforced polymer (CFRP) plate is the weakest link and fatigue performance is a major consideration. This paper gives details of a fatigue test programme of a series of small-scale steel beams bonded with a CFRP plate. Two phases of the fatigue life, including crack initiation life and crack propagation life, are considered. Backface-strain technique was applied to monitor crack initiation. An S-N curve was developed from the test results. The curve correlates the maximum principal interfacial stress at the plate end to the crack initiation life. The fatigue limit of the S-N curve was found to be about 30% of the ultimate static failure stress. In accordance with Paris Law, moreover, an equation was developed to predict the number of cycles during the crack propagation. The empirical coefficients of the equation were obtained from the fatigue test results. This equation can correctly predict the crack propagation life. The fatigue load range affects the fatigue life, but its significance is much less than the magnitude of the maximum load in the load range.

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