Adhesive and cohesive failure analyses of bonded FRP composite tubular T-joints in combined axial compression and out-of-plane bending

Abstract

Tubular T-joints are the most widely used structural connectors. FRP composites, with their superior intrinsic properties, can be a more suitable choice than steel. Computational fracture mechanics has been employed to develop finite element models for predicting adhesive and cohesive failures in bonded composite T-joints under combined loading, with clamped chord and brace. Three-dimensional stress analysis, in conjunction with appropriate failure criteria (Tsai-Wu for adhesive failure and parabolic yield for cohesive failure), revealed that the saddle point (β = 0°) along the bottom toe line and middle fillet line of the bonded T-joint is particularly prone to adhesive and cohesive failures, respectively. Fracture growth analysis using VCCT demonstrated a predominant radial propagation of both adhesive and cohesive failures, primarily governed by opening mode. Simultaneous failure growth leads to mutual retardation, with cohesive failure significantly contributing to the suppression of adhesive failure propagation. Despite the interaction effects, fracture propagation within the bonded T-joint has intensified local stress concentrations, adversely impacting the structural integrity of the joint. Structural integrity of bonded T-joints to adhesive failure can be enhanced by using a circumferentially oriented ([0]₁₆) brace along with a cross-ply ([0/90]_4S) chord for smaller cracks (a_a/f_b ≤ 0.3), while circumferential ([0]₁₆) chord for larger cracks (a_a/f_b ≤ 0.3). Circumferentially ([0]₁₆) oriented fiber reinforced brace and chord are proposed for improving the overall joint fracture resistance against simultaneous influence of adhesive and cohesive failures.

Keywords

adhesive failure cohesive failure FRP composites SERR tubular T-joints VCCT

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References

Chon

. Analysis of tubular lap joint in torsion. J Compos Mater 1982; 16: 268–284.

Hipol

. Analysis and optimization of a tubular lap joint subjected to torsion. J Compos Mater 1984; 18: 298–311.

Yang

Huang

Guan

. Stress model of composite pipe joints under bending. J Compos Mater 2002; 36: 1331–1348.

Zou

Taheri

. Stress analysis of adhesively bonded sandwich pipe joints subjected to torsional loading. Int J Solid Struct 2006; 43: 5953–5968.

. Nonlinear analysis of adhesively bonded tubular single-lap joints for composites in torsion. Compos Sci Technol 2007; 67: 1320–1329.

. Strength prediction of tubular composite adhesive joints under torsion. Compos Sci Technol 2007; 67: 1340–1347.

. Torque capacity of tubular adhesive joints with different composite adherends. Mater Lett 2008; 62: 1234–1237.

Hosseinzadeh

Taheri

. Non-linear investigation of overlap length effect on torsional capacity of tubular adhesively bonded joints. Compos Struct 2009; 91: 186–195.

Yang

Guan

. Stress analysis of composite pipe joints under combined torsional and tensile loading. J Pressure Vessel Technol 2009; 131: 051210.

10.

. Finite difference three-dimensional solution of stresses in adhesively bonded composite tubular joint subjected to torsion. Int J Adhesion Adhes 2010; 30: 191–199.

11.

Parashar

Mertiny

. Failure mechanism in adhesively bonded FRP pipe sections with different fibre architecture. Compos B Eng 2013; 47: 102–106.

12.

de Queiroz

Banea

. Methods to increase the mechanical performance of composite adhesive joints: An overview with focus on joints with natural fibre composite adherends. J Compos Mater 2022; 56: 3993–4010.

13.

Hashim

Cowling

Lafferty

. The integrity of bonded joints in large composite pipes. Int J Adhesion Adhes 1998; 18: 421–429.

14.

Esmaeel

Taheri

. Stress analysis of tubular adhesive joints with delaminated adherend. J Adhes Sci Technol 2009; 23: 1827–1844.

15.

Esmaeel

Taheri

. Influence of adherend’s delamination on the response of single lap and socket tubular adhesively bonded joints subjected to torsion. Compos Struct 2011; 93: 1765–1774.

16.

Das

Pradhan

. Adhesion failure analyses of bonded tubular single lap joints in laminated fibre reinforced plastic composites. Int J Adhesion Adhes 2010; 30: 425–438.

17.

Das

Pradhan

. Finite element based design and adhesion failure analysis of bonded tubular socket joints made with laminated FRP composites. J Adhes Sci Technol 2011; 25: 41–67.

18.

Das

Pradhan

. Delamination damage analysis of laminated bonded tubular single lap joint made of fiber-reinforced polymer composite. Int J Damage Mech 2014; 23: 772–790.

19.

Kumar

Noor

, et al. FEM based delamination damage analysis of bonded FRP composite pipe joints. ISSS J Micro Smart Syst 2018; 7: 45–51.

20.

Dalfi

Jan

Yousaf

, et al. Improving the impact resistance and damage tolerance of fibre reinforced composites: a review. J Compos Mater 2023; 57: 4479–4500.

21.

Goda

Padayodi

Raoelison

. Enhancing fiber/matrix interface adhesion in polymer composites: mechanical characterization methods and progress in interface modification. J Compos Mater 2024; 58: 3077–3110.

22.

Kumar

Das

. Adhesion failure analyses of laminated FRP composite made bonded tubular T-joints with axially compressed brace. Compos Struct 2021; 258: 113386.

23.

Kumar

Das

. Fracture analyses of bonded tubular FRP composite K-joints with braces subjected to balanced axial load. J Braz Soc Mech Sci Eng 2022; 44: 251.

24.

Rashnooie

Zeinoddini

Ghafoori

, et al. Experimental and numerical study on the in-plane bending behaviour of FRP-strengthened steel tubular welded T-joints. Thin-Walled Struct 2024; 201: 112000.

25.

Hellier

Connolly

Kare

, et al. Prediction of the stress distribution in tubular Y-and T-joints. Int J Fatig 1990; 12: 25–33.

26.

Yeoh

S-K

Soh

A-K

Soh

C-K

. Behaviour of tubular T-joints subjected to combined loadings. Journal of Constructional Steel Research 1995; 32: 259–280.

27.

Pang

Lee

. Three-dimensional finite element analysis of a tubular T-joint under combined axial and bending loading. Int J Fatig 1995; 17: 313–320.

28.

De Moura

Campilho

Gonçalves

. Crack equivalent concept applied to the fracture characterization of bonded joints under pure mode I loading. Compos Sci Technol 2008; 68: 2224–2230.

29.

Behera

Parida

Das

. Effect of pre-embedded adhesion failures and surface ply delaminations on the structural integrity of adhesively bonded single lap joints made with curved laminated FRP composite panels. Int J Adhesion Adhes 2021; 108: 102887.

30.

Cope

Pipes

. Design of the composite Spar-Wingskin joint. Composites 1982; 13: 47–53.

31.

Das

Baishya

. Failure analysis of bonded composite pipe joints subjected to internal pressure and axial loading. Procedia Eng 2016; 144: 1047–1054.

32.

Mishra

Pradhan

Pandit

. Adhesion failure propagation analyses of Spar Wingskin Joints made with curved laminated FRP composite and FGM panels. Int J Adhesion Adhes 2018; 85: 77–87.

33.

Panigrahi

Pradhan

. Onset and growth of adhesion failure and delamination induced damages in double lap joint of laminated FRP composites. Compos Struct 2008; 85: 326–336.

34.

Kaw

. Mechanics of composite materials. CRC Press, 2005.

35.

Sitnikova

Liang

, et al. The Tsai-Wu failure criterion rationalised in the context of UD composites. Compos Appl Sci Manuf 2017; 102: 207–217.

36.

Tsai

. A general theory of strength for anisotropic materials. J Compos Mater 1971; 5: 58–80.

37.

Raghava

Caddell

Yeh

. The macroscopic yield behaviour of polymers. J Mater Sci 1973; 8: 225–232.

38.

Rybicki

Kanninen

. A finite element calculation of stress intensity factors by a modified crack closure integral. Eng Fract Mech 1977; 9: 931–938.