Finite element model updating of bolted lap joints implementing identification of joint affected region parameters

Shokrollahi, Saeed; Adel, Farhad

doi:10.22064/tava.2016.19385

Finite element model updating of bolted lap joints implementing identification of joint affected region parameters

Authors

Saeed Shokrollahi ¹
Farhad Adel ²

¹ Aerospace complex, Malek-Ashtar University of Technology, Tehran, Iran

² PhD Candidate ,Aerospace complex, Malek-Ashtar University of Technology, Tehran, Iran

10.22064/tava.2016.19385

Abstract

In this research, the new concept of ‘bolted joint affected region (BJAR)’ is introduced to simulate dynamical behavior of bolted lap joints. Such regions are modeled via special elements called contact zone element (CZE) which unify the neighboring contact surfaces of substructures. These elements are different from the thin layer interface elements that form an individual layer between the two substructures. The CZEs have no specified elastic characteristics. They are thus different from the adjoining solid elements and the constitutive relation for them is prescribed in normal and shear components. The unknown parameters of the model can be identified throughout model updating with modal test data. The structure’s frequency response function (FRF) is measured by excitation with an impact hammer and the measured responses are compared with model predictions including the CZEs’ parameters. The difference between the measured and predicted frequencies is minimized as the objective function. The optimized thickness and density are considered in addition to the elastic properties of BJAR. The competency of the proposed procedure is verified with modeling an actual structure containing a single lap bolted joint coupling two identical structural steel beams. The results showed proper conformity with model predictions. This model can be incorporated into the commercial finite element codes to simulate bolted joints for large and complex structures considering its accuracy and computationally efficient manner

Highlights

Finite element modeling of bolted lap joints for a beam structure is considered.
'Bolted Joint Affected Region' concept and contact zone elements are introduced.
Natural frequencies of the bolted structure are measured through modal testing.
F.E. models are updated through a genetic algorithm.
Thickness and density of the BJAR are identified as well as the Young’s modulus.

Keywords

Main Subjects

Modal analysis

References

[1] I. Zaman, A. Khalid, B. Manshoor, S. Araby, M.I. Ghazali, The effects of bolted joints on dynamic response of structures, IOP Conference Series: Materials Science and Engineering, 50 (No. 0120218) (2013).

[2] J.L. Dohner, On the development of methodologies for constructing predictive models of structures with joints and interfaces, Sandia National Laboratories, Technical Report No. SAND2001-0003P, (2001).

[3] J. Kim, J.C. Yoon, B.S. Kang, Finite element analysis and modeling of structure with bolted joints, Applied Mathematical Modelling, 31 (2007) 895-911.

[4] R.A. Ibrahim, C.L. Pettit, Uncertainties and dynamic problems of bolted joints and other fasteners, Journal of Sound and Vibration, 279 (2005) 857-936.

[5] K.T. Yang, Y.S. Park, Joint structural parameter identification using a subset of frequency response function measurements, Mechanical Systems and Signal Processing, 7 (1993) 509-530.

[6] H. Ahmadian, H. Jalali, Identification of bolted lap joints parameters in assembled structures, Mechanical Systems and Signal Processing, 21 (2007) 1041-1050.

[7] F. Gant, P. Rouch, F. Louf, L. Champaney, Definition and updating of simplified models of joint stiffness, International Journal of Solids and Structures, 48 (2011) 775-784.

[8] J.E. Mottershead, M.I. Friswell, G.H.T. Ng, J.A. Brandon, Geometric parameters for finite element model updating of joints and constraints, Mechanical Systems and Signal Processing, 10 (1996) 171-182.

[9] H. Ahmadian, H. Jalali, Generic element formulation for modelling bolted lap joints, Mechanical Systems and Signal Processing, 21 (2007) 2318-2334.

[10] H. Ahmadian, J.E. Mottershead, S. James, M.I. Friswell, C.A. Reece, Modelling and updating of large surface-to-surface joints in the AWE-MACE structure, Mechanical Systems and Signal Processing, 20 (2006) 868-880.

[11] D.J. Segalman, A four-parameter Iwan model for lap-type joints, Journal of Applied Mechanics, 72 (2005) 752-760.

[12] I.I. Argatov, E.A. Butcher, On the Iwan models for lap-type bolted joints, International Journal of Non-Linear Mechanics, 46 (2011) 347-356.

[13] S. Bograd, P. Reuss, A. Schmidt, L. Gaul, M. Mayer, Modeling the dynamics of mechanical joints, Mechanical Systems and Signal Processing, 25 (2011) 2801-2826.

[14] Y. Amir, S. Govindarajan, S. Iyyanar, Bolted joints modeling techniques, analytical, stochastic and FEA comparison, in: ASME International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers, 2012, pp. 777-788.

[15] H. Jalali, Linear contact interface parameter identification using dynamic characteristic equation, Mechanical Systems and Signal Processing, 66 (2016) 111-119.

[16] R.E. Goodman, R.L. Taylor, T.L. Brekke, A model for the mechanics of jointed rock, Journal of Soil Mechanics & Foundations Div, 59 (1968) 99-137.

[17] C.S. Desai, M.M. Zaman, J.G. Lightner, H.J. Siriwardane, Thin‐layer element for interfaces and joints, International Journal for Numerical and Analytical Methods in Geomechanics, 8 (1984) 19-43.

[18] G. Beer, An isoparametric joint/interface element for finite element analysis, International journal for numerical methods in engineering, 21 (1985) 585-600.

[19] K.G. Sharma, C.S. Desai, Analysis and implementation of thin-layer element for interfaces and joints, Journal of engineering mechanics, 118 (1992) 2442-2462.

[20] R.A. Day, D.M. Potts, Zero thickness interface elements—Numerical stability and application, International Journal for numerical and analytical methods in geomechanics, 18 (1994) 689-708.

[21] D.M. Potts, L. Zdravkovic, Finite element analysis in geotechnical engineering: Application, Thomas Telford, London, 2001.

[22] H. Ahmadian, M. Ebrahimi, J.E. Mottershead, M.I. Friswell, Identification of bolted-joint interface models, in: Proceedings of ISMA, Katholieke University, Leuven, Belgium, 2002, pp. 1741-1747.

[23] H. Ahmadian, H. Jalali, J.E. Mottershead, M.I. Friswell, Dynamic modeling of spot welds using thin layer interface theory, in: 10th International Congress on Sound and Vibration, Stockholm, Sweden, 2003, pp. 7-10.

[24] S. Bograd, A. Schmidt, L. Gaul, Joint damping prediction by thin layer elements, in: Proceedings of the IMAC 26th Society of Experimental Mechanics Inc. , Bethel, CT, 2008.

[25] G.N. Pande, K.G. Sharma, On joint/interface elements and associated problems of numerical ill‐conditioning, International Journal for Numerical and Analytical Methods in Geomechanics, 3 (1979) 293-300.

[26] H. Jalali, A. Hedayati, H. Ahmadian, Modelling mechanical interfaces experiencing micro-slip/slap, Inverse Problems in Science and Engineering, 19 (2011) 751-764.

[27] M. Iranzad, H. Ahmadian, Identification of nonlinear bolted lap joint models, Computers & Structures, 96 (2012) 1-8.