and Applied Mechanics
57, 1, pp. 49-58, Warsaw 2019
DOI: 10.15632/jtam-pl.57.1.49
Investigation of flexibility constants for a multi-spring model: a solution for buckling of cracked micro/nanobeams
under axial compressive load based on a modified couple stress theory. This model inc-
ludes an equivalent rotational spring to transmit the bending moment and an equivalent
longitudinal spring to transmit the axial force through the cracked section, which leads to
promotion of the modelling of discontinuities due to the presence of the crack. Moreover,
this study considers coupled effects between the bending moment and axial force on the
discontinuities at the cracked section. Therefore, four flexibility constants appear in the con-
tinuity conditions. In this paper, these four constants are obtained as a function of crack
depth, separately. This modelling is employed to solve the buckling problem of cracked
micro/nanobeams using a close-form method, Euler-Bernoulli theory and simply suppor-
ted boundary conditions. Finally, the effects of flexibility constants, crack depth and crack
location on the critical buckling load are studied.
References
Akbarzadeh Khorshidi M., Shaat M., Abdelkefi A., Shariati M., 2017, Nonlocal modeling
and buckling features of cracked nanobeams with von Karman nonlinearity, Applied Physics A:
Material Science and Processing, 123, 62
Akbarzadeh Khorshidi M., Shariati M., 2017a, A multi-spring model for buckling analysis
of cracked Timoshenko nanobeams based on modified couple stress theory, Journal of Theoretical
and Applied Mechanics, 55, 4, 1127-1139
Akbarzadeh Khorshidi M., Shariati M., 2017b, Buckling and postbuckling of size-dependent
cracked microbeams based on a modified couple stress theory, Journal of Applied Mechanics and
Technical Physics, 58, 4, 717-724
Gross B., Srawley J.E., 1965, Stress-intensity factors for single edge notch specimens in bending
or combined bending and tension by boundary collocation of a stress function, NASA Technical
Note, D-2603
Hasheminejad M., Gheshlaghi B., Mirzaei Y., Abbasion S., 2011, Free transverse vibrations
of cracked nanobeams with surface effects, Thin Solid Films, 519, 2477-2482
Hsu J.Ch., Lee H.L., Chang W.J., 2011, Longitudinal vibration of cracked nanobeams using
nonlocal elasticity theory, Current Applied Physics, 11, 1384-1388
Hu K.M., Zhang W.M., Peng Z.K., Meng G., 2016, Transverse vibrations of mixed-mode
cracked nanobeams with surface effect, Journal of Vibration and Acoustics, 138, 1, 011020
Irwin G.R., 1960, Fracture mechanics, [In:] Structural Mechanics, J.N. Goodier, and N.J. Hoff
(Edit.), Pergamon Press, p. 557
Joshi A.Y., Sharma S.C., Harsha S., 2010, Analysis of crack propagation in fixed-free single-
walled carbon nanotube under tensile loading using XFEM, ASME Journal of Nanotechnology in
Engineering and Medicine, 1, 4, 041008
Ke L.L., Yang J., Kitipornchai S., 2009, Postbuckling analysis of edge cracked functionally
graded Timoshenko beams under end shortening, Composite Structures, 90, 152-160
Loya J.A., Aranda-Ruiz J., Fernandez-Saez J., 2014, Torsion of cracked nanorods using a
nonlocal elasticity model, Journal of Physics D: Applied Physics, 47, 115304 (12pp)
Loya J.A., Rubio L., Fernandez-Saez J., 2006, Natural frequencies for bending vibrations of
Timoshenko cracked beams, Journal of Sound and Vibration, 290, 640-653
Loya J., Lopez-Puente J., Zaera R., Fernandez-Saez J., 2009, Free transverse vibrations
of cracked nanobeams using a nonlocal elasticity model, Journal of Applied Physics, 105, 044309
Mohammad-Abadi M., Daneshmehr A.R., 2014, Size dependent buckling analysis of micro-
beams based on modified couple stress theory with high order theories and general boundary
conditions, International Journal of Engineering Science, 74, 1-14
Rice J.R., Levy N., 1972, The part-through surface crack in an elastic plate, Journal of Applied
Mechanics: Transaction of the ASME, March, 185-194
Shaat M., Akbarzadeh Khorshidi M., Abdelkefi A., Shariati M., 2016, Modeling and
vibration characteristics of cracked nano-beams made of nanocrystalline materials, International
Journal of Mechanical Sciences, 115-116, 574-585
Torabi K., Nafar Dastgerdi J., 2012, An analytical method for free vibration analysis of
Timoshenko beam theory applied to cracked nanobeams using a nonlocal elasticity model, Thin
Solid Films, 520, 6595-6602
Tsai J.L., Tzeng S.H., Tzou Y.J., 2010, Characterizing the fracture parameters of a graphene
sheet using atomistic simulation and continuum mechanics, International Journal of Solids and
Structures, 47, 3, 503-509
Wang Q., Quek S.T., 2005, Repair of cracked column under axially compressive load via piezo-
electric patch, Computers and Structures, 83, 1355-1363
Wang K., Wang B., 2013, Timoshenko beam model for the vibration analysis of a cracked
nanobeam with surface energy, Journal of Vibration and Control, 21, 12, 2452-2464
Yang J., Cheng Y., 2008, Free vibration and buckling analyses of functionally graded beams
with edge cracks, Composite Structures, 83, 48-60
Yang F., Chong A.C.M., Lam D.C.C., Tong P., 2002, Couple stress based strain gradient
theory for elasticity, International Journal of Solids and Structures, 39, 2731-2743