Residual stress analysis of riveting process using finite element method

Download
2007
Karasan, M Murat
Rivets are widely used as a means of fastening in airframe construction industry. There are various types of riveted joints on an aircraft fuselage or on a helicopter body. Among the other types of fasteners riveted joints are preferred in such applications due to; their permanence after installation and their economical advantages. In a riveted joint, it is known that residual stresses are present as a result of the installation process. Furthermore, during the flight of an aircraft, the fuselage is loaded in one cycle and such cycles are repeated throughout the service life. As a result, the panels and the rivets are subjected to fatigue type loading. The integrity of the joint must be maintained against this combination of service loads and the residual stresses. Hence, the riveting process parameters which influence the residual stresses are utmost critical in terms of fatigue life of the hole body. In this study it is aimed to obtain an accurate numerical model of a single-lap riveted joint which is widely used in airframes. 2-D axisymmetrical and 3-D numerical models are generated using commercial finite element code ABAQUS/CAE and subsequent parametric studies are carried out on these models. The Results of both models are compared with those found in the literature. Clearance between hole and rivet shank is selected as the primary parameter to be inspected. The effects of hole clearance on the final residual stress field are examined on 2-D and 3D models. Furthermore, a through the thickness, crack on the inner panel which is initiated after installation is modeled. The crack is perpendicular to the direction of loading. It is placed to the residual tensile stress zone that surrounds the rivet hole. Hence, the effects of residual stresses are also taken into account. For a riveted joint subjected to fatigue loading, such a macroscopic crack could eventually form. In this thesis, stress intensity factors (SIF’s) for this crack are calculated for various parameters such as clearance and crack length. These can be utilized in a subsequent fatigue crack growth analysis as the initial values or they can be used in a fracture analysis, to predict unstable crack growth due to overload (i.e. crack linking).

Suggestions

Design and analysis of fixturing in assembly of sheet metal components of helicopters
Bayar, Fatih Mehmet; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2007)
Assembling of the compliant parts used in aviation industry is a challenging process. Assembly fixtures are quite important tools in this effort and widely used in industry. In fixturing of easily deformable sheet metal parts, besides restraining the rigid body motion of the parts, the possible deformations that may occur during the assembly process and the spring-back effect on the final product need to be taken in to consideration. In order to guarantee a successful assembling, in other words, to obtain t...
Parameter Identification of Riveted Joints Using Vibration Methods
Altuntop, Elif; Aykan, Murat; Şahin, Melin (2015-02-05)
Rivets are widely used in several industries including aerospace, shipbuilding and construction. Aircraft components such as wings and fuselages are some examples of riveted structures. Accurate parameter identification of these joints is critical since excessive number of rivets is present in such structures. Furthermore, modeling structures with fasteners has always been a challenge since these members might show nonlinear behavior. In this study, the FEM of a continuous plate is constructed and modal tes...
Investigation of wear behavior of aged and non-aged SiC-reinforced AlSi7Mg2 metal matrix composites in dry sliding conditions
ÇELİK, YAHYA HIŞMAN; Demir, Mehmet Emin; KILIÇKAP, EROL; Kalkanlı, Ali (Springer Science and Business Media LLC, 2020-01-01)
Metal matrix composites (MMCs) with their splendid mechanical properties have been specifically designed for use in fields such as aerospace and aviation. The presence of hard ceramic particles in MMC increases the hardness of the matrix product and decreases its coefficient of friction. Therefore, the wear resistance is improved. Moreover, the mechanical properties of these composite materials can be improved by applying heat treatments. In this study, AlSi7Mg2 MMCs with 15 wt% SiC reinforcement were produ...
Composite shear stud strength at early concrete ages
Topkaya, Cem; Williamson, EB (American Society of Civil Engineers (ASCE), 2004-06-01)
Composite action between a reinforced concrete deck and steel girders is usually achieved by making use of welded headed shear studs. The mechanics of shear studs embedded in mature concrete has been investigated extensively in the past. Current literature, however, lacks experimental evidence of steel-concrete interface behavior at early concrete ages. This information is useful in understanding the behavior of bridges during construction. Current testing methods are not suitable for determining the respon...
Stress and fracture analysis of riveted joints
Keçelioğlu, Galip; Dağ, Serkan; Department of Mechanical Engineering (2008)
The objective of this study is to model and analyze a three dimensional single riveted lap joint (with and without a crack). By using finite element method, stress and fracture analyses are carried out under both the residual stress field and external tensile loading. Using a two step simulation, riveting process and subsequent tensile loading of the lap joint are simulated to determine the residual and overall stress state. Residual stress state due to riveting is obtained by interference and clamping misf...
Citation Formats
M. M. Karasan, “Residual stress analysis of riveting process using finite element method,” M.S. - Master of Science, Middle East Technical University, 2007.