International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: 06 86 115306-5757 IJET-IJENS @ December 2011 IJENS I J E N S Abstract— A three-dimensional finite element modeling is developed using ABAQUS ® software. This includes riveted and rivet-bonded joints models. Both models undergo thermal heat caused by hot-driven rivet process and then are subjected to a constant velocity at one of its strip edges to simulate the shear tensile test up to the failure point. The developed FE models were based on elastic-plastic properties and ductile fracture limit criteria. In addition, the adhesive layer was modeled based on traction separation. Detailed experiments were conducted to evaluate these material properties and provide the FE developed models with these necessary data. The thermal stresses developed in riveted and rivet-bonded joints are assessed and reported. The present work shows that introducing an adhesive layer to riveted joints vastly reduces the stresses developed in these joints. In addition, the complete load-displacement curve for each joining model is obtained and compared with the finite element models without including the effect of thermal analysis. Index Term— Adhesive Layer, Load-Displacement Curve, Rivet, Rivet-Bonded, Thermal Stresses. I. INTRODUCTION Rivets are used in many design applications such as joining together two plates. A full understanding of these joints is essential in most of automobile and aerospace industries. When a rivet is heated before being placed in the hole, it is identified as hot-driven rivet. After the rivet colds, it presses the connected parts strongly and the rivet pole expands to fill the hole. Thus, the rivet head becomes under high concentration of stresses, which the rivet has to resist. The sharp corner beneath the head may cause the head to be failed. Tearing between the rivet holes, shearing, or crushing of the rivet and/ or the joined material are considered to be the major tension connection failures. Using an adhesive material as bonding is another way of joining two different parts. It is used to adhere a wide range of materials structure such as metal to metal or metal to non-metal. It has the advantages of reducing stress concentration, resisting fatigue, and the capability of joining two different thickness materials as well as joining two dissimilar materials. Bonded structure could be used alone or together with a mechanical This work was supported by College of Engineering Research Center, King Saud University. Essam A. Al-Bahkali is with the Mechanical Engineering Department, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia (phone: +9661-4676675; fax: +9661-67-6652; e-mail: [email protected]). connection. The bonded with a mechanical connection type may include weld-bonded and rivet-bonded connections. Barron [1] investigated the effect of clamping forces and grip on the fatigue strength of rivets in butt joints. Hoffer [2] determined the load-bearing capacity of a riveted joint by using statistical analysis. He also evaluated the type of the joint failures. Schvechkov [3] studied experimentally the effects of adhesive mechanical properties along with the geometry of butted sheets on the point of failure and cycle longevity on rivet-bonded joints. Fung and Smart [4] examined countersunk and snap riveted single lap joints experimentally and numerically. They studied the failures metallurgically to determine the cause of failure and then they analyzed the joints using the finite element method. They found that the stress concentration for this joint occurred at a point away from the point of failure of a riveted joint. They also determined the stress patterns around the rivet. Bedaira and Eastaugh [5] proposed a numerical procedure for the analysis of riveted lap joints taking into account the effect of the secondary out of plane bending and plates/rivet interaction. Their results showed that the secondary bending largely affects the maximum tensile and compressive stresses within the joint with difference might reach up to 39%. They also presented an experimental comparison using photo-elastic test. Gomeza et al. [6] presented a mechanical model to reproduce the behavior of a structural hybrid adhesive/riveted single lap joint. They used the Bond-Graph technique in order to obtain the equations of the model. These equations depended on four parameters considered to be the characteristics of the joint. Their model reproduced the experimental curves with great precision. Sadowski et al. [7] carried out an experimental investigations of steel adhesive double lap joints reinforced by rivets. They monitored the deformation process of the hybrid joint using digital image correlation system. They also studied the model numerically and analyzed the whole model behavior up to failure point. They found that adding a rivet to the adhesive joint led to very significant energy absorption by about 35% in comparison to a simple adhesive. Moroni et al. [8] evaluated the beneficial of using hybrid weld-, rivet- or clinch-bonded joints in comparison with simple adhesive, spot-welded, riveted or clinched joints. They conducted experimental analysis using the design of experiments methodology. The influence of the material, geometrical factors, and environment on static strength, stiffness and energy absorption was assessed through the Finite Element Modeling for Thermal Stresses Developed in Riveted and Rivet-Bonded Joints Essam A. Al-Bahkali
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International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: 06 86
115306-5757 IJET-IJENS @ December 2011 IJENS I J E N S
Abstract— A three-dimensional finite element modeling is
developed using ABAQUS® software. This includes riveted and
rivet-bonded joints models. Both models undergo thermal heat
caused by hot-driven rivet process and then are subjected to a
constant velocity at one of its strip edges to simulate the shear
tensile test up to the failure point. The developed FE models were
based on elastic-plastic properties and ductile fracture limit
criteria. In addition, the adhesive layer was modeled based on
traction separation. Detailed experiments were conducted to
evaluate these material properties and provide the FE developed
models with these necessary data. The thermal stresses developed
in riveted and rivet-bonded joints are assessed and reported. The
present work shows that introducing an adhesive layer to riveted
joints vastly reduces the stresses developed in these joints. In
addition, the complete load-displacement curve for each joining
model is obtained and compared with the finite element models
without including the effect of thermal analysis.
Index Term— Adhesive Layer, Load-Displacement Curve,
Rivet, Rivet-Bonded, Thermal Stresses.
I. INTRODUCTION
Rivets are used in many design applications such as joining
together two plates. A full understanding of these joints is
essential in most of automobile and aerospace industries.
When a rivet is heated before being placed in the hole, it is
identified as hot-driven rivet. After the rivet colds, it presses
the connected parts strongly and the rivet pole expands to fill
the hole. Thus, the rivet head becomes under high
concentration of stresses, which the rivet has to resist. The
sharp corner beneath the head may cause the head to be failed.
Tearing between the rivet holes, shearing, or crushing of the
rivet and/ or the joined material are considered to be the major
tension connection failures.
Using an adhesive material as bonding is another way of
joining two different parts. It is used to adhere a wide range of
materials structure such as metal to metal or metal to non-metal.
It has the advantages of reducing stress concentration, resisting
fatigue, and the capability of joining two different thickness
materials as well as joining two dissimilar materials. Bonded
structure could be used alone or together with a mechanical
This work was supported by College of Engineering Research Center,
King Saud University. Essam A. Al-Bahkali is with the Mechanical Engineering Department,
King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia (phone: