Abstract
The first-order shear deformable beam theory should be named after Stephen Timoshenko and Paul Ehrenfest in recognition of the significant contribution of both of them. The Timoshenko–Ehrenfest beam model can predict the flexure mechanics of short stubby beams with adequate accuracy if it has been enriched with a proper shear coefficient. The shear coefficient lies at the heart of the Timoshenko–Ehrenfest beam theory was apparently first introduced by Friedrich Engesser in the nineteenth century. Detecting the appropriate formula of the shear coefficient for solid rectangular cross-sections was surprisingly a challenging issue in the literature. A stationary variational framework of the Timoshenko–Ehrenfest beam, founded on the elasticity theory, is conceived and applied to set forth the variationally consistent shear coefficient of a prismatic beam of a solid rectangular cross-section. Evidence of efficacy of the introduced shear coefficient is illustrated as the intrinsic anomalies of the counterpart shear coefficients are thoroughly discussed. The present study may pave the way ahead in appreciating the significance of implementing the apposite formula of the shear coefficient associated with the Timoshenko–Ehrenfest beam theory.
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Abbreviations
- A :
-
Cross-sectional area
- \({\mathfrak{A}}\) :
-
Rectangular cross-section
- \({\mathbf{b}}\) :
-
Body force
- b :
-
Half width of cross-section
- \({\mathcal{B}}\) :
-
General bounded region
- \(\partial {\mathcal{B}}\) :
-
Closed boundary of the region
- \({\mathbf{E}}\) :
-
Strain field
- E :
-
Young’s modulus
- \(\Im\) :
-
Stationary variational functional
- G :
-
Shear modulus
- h :
-
Half height of cross-section
- I :
-
Second area moment of the cross-section
- \(k\) :
-
Shear coefficient
- \(\ell\) :
-
Length of beam
- m :
-
Distributed bending couple
- M :
-
Flexural moment field
- q :
-
Distributed transversal loading
- \({\mathbb{S}}\) :
-
Compliance tensor of elasticity
- \({\mathbf{t}}\) :
-
Surface traction
- \({\mathbf{T}}\) :
-
Stress field of the inflected elastic beam
- \(u\) :
-
Centroidal deflection
- \({\mathbf{u}}\) :
-
Displacement field of the beam
- \(V\) :
-
Distribution of the shear force
- \(x,y,z\) :
-
Cartesian orthogonal coordinates
- \(\chi\) :
-
Auxiliary parameter
- \(\nu\) :
-
Poisson’s ratio
- \(\rho\) :
-
Destiny of the beam
- \(\psi\) :
-
Total rotation in the x–z plane
- \(\zeta\) :
-
Aspect ratio of the rectangle
- \(\Upsilon\) :
-
Shear flexibility of the cross-section
References
Sladek J, Sladek V, Xu M, Deng Q (2021) A cantilever beam analysis with flexomagnetic effect. Meccanica 56:2281–2292. https://doi.org/10.1007/s11012-021-01357-9
Faghidian SA (2021) Contribution of nonlocal integral elasticity to modified strain gradient theory. Eur Phys J Plus 136:559. https://doi.org/10.1140/epjp/s13360-021-01520-x
Faghidian SA (2021) Flexure mechanics of nonlocal modified gradient nanobeams. J Comput Des Eng 8:949–959. https://doi.org/10.1093/jcde/qwab027
Banerjee A (2020) Non-dimensional analysis of the elastic beam having periodic linear spring mass resonators. Meccanica 55:1181–1191. https://doi.org/10.1007/s11012-020-01151-z
Failla G, di Paola M, Pirrotta A, Burlon A, Dunn I (2019) Random vibration mitigation of beams via tuned mass dampers with spring inertia effects. Meccanica 54:1365–1383. https://doi.org/10.1007/s11012-019-00983-8
Adam C, di Lorenzo S, Failla G, Pirrotta A (2017) On the moving load problem in beam structures equipped with tuned mass dampers. Meccanica 52:3101–3115. https://doi.org/10.1007/s11012-016-0599-4
Numanoğlu HM, Ersoy H, Civalek Ö, Ferreira AJM (2021) Derivation of nonlocal FEM formulation for thermo-elastic Timoshenko beams on elastic matrix. Compos Struct 273:114292. https://doi.org/10.1016/j.compstruct.2021.114292
Failla G, Sofi A, Zingales M (2015) A new displacement-based framework for non-local Timoshenko beams. Meccanica 50:2103–2122. https://doi.org/10.1007/s11012-015-0141-0
Pirrotta A, Cutrona S, di Lorenzo S (2015) Fractional visco-elastic Timoshenko beam from elastic Euler–Bernoulli beam. Acta Mech 226:179–189. https://doi.org/10.1007/s00707-014-1144-y
Sofi A, Muscolino G, Elishakoff I (2015) Static response bounds of Timoshenko beams with spatially varying interval uncertainties. Acta Mech 226:3737–3748. https://doi.org/10.1007/s00707-015-1400-9
Laura PAA, Rossi RE, Maurizi MJ (1992) Vibrating Timoshenko beams, a tribute to the 70th anniversary of the publication of Professor S. Timoshenko’s epoch making contribution, Institute of Applied Mechanics and Department of Engineering, Universidad Nacional del Sur, Bahia Blanca, Argentina
Koiter WT (1976) Some comments on the so-called Timoshenko beam theory. Report No. 597, Laboratory of Technical Mechanics, Delft University of Technology
Elishakoff I (2019) Who developed the so-called Timoshenko beam theory. Math Mech Solids 25:97–116. https://doi.org/10.1177/1081286519856931
Elishakoff I, Kaplunov J, Nolde E (2015) Celebrating the centenary of Timoshenko’s study of effects of shear deformation and rotary inertia. Appl Mech Rev 67:060802. https://doi.org/10.1115/1.4031965
Elishakoff I (2018) JP Den Hartog about SP Timoshenko: fifty years later. Math Mech Solids 24:1340–1348. https://doi.org/10.1177/1081286518792959
Elishakoff I (2019) Stepan Prokofievich Timoshenko and America. ZAMM J Appl Math Mech 99:e201800338. https://doi.org/10.1002/zamm.201800338
Challamel N, Elishakoff I (2019) A brief history of first-order shear-deformable beam and plate models. Mech Res Commun 102:103389. https://doi.org/10.1016/j.mechrescom.2019.06.005
Eisenberger M (2003) Dynamic stiffness vibration analysis using a high-order beam element. Int J Numer Methods Eng 57:1603–1614. https://doi.org/10.1002/nme.736
Reddy JN (1984) A simple higher-order theory for laminated composite plates. J Appl Mech 51:745–752. https://doi.org/10.1115/1.3167719
Polizzotto C (2015) From the Euler–Bernoulli beam to the Timoshenko one through a sequence of Reddy-type shear deformable beam models of increasing order. Eur J Mech A Solids 53:62–74. https://doi.org/10.1016/j.euromechsol.2015.03.005
Carrera E, Brischetto S, Nali P (2011) Plates and shells for smart structures, United Kingdom. Wiley, New York
Carrera E, Cinefra M, Petrolo M, Zappino E (2014) Finite element analysis of structures through unified formulation, United Kingdom. Wiley, New York
Carrera E, Zozulya VV (2021) Closed-form solution for the micropolar plates: Carrera unified formulation (CUF) approach. Arch Appl Mech 91:91–116. https://doi.org/10.1007/s00419-020-01756-6
Carrera E, Zozulya VV (2021) Carrera unified formulation (CUF) for the micropolar beams: analytical solutions. Mech Adv Mater Struct 28:583–607. https://doi.org/10.1080/15376494.2019.1578013
Carrera E, Didem Demirbas M (2021) Evaluation of bending and post-buckling behavior of thin-walled FG beams in geometrical nonlinear regime with CUF. Compos Struct 275:114408. https://doi.org/10.1016/j.compstruct.2021.114408
Cinefra M, Moruzzi MC, Bagassi S, Zappino E, Carrera E (2021) Vibro-acoustic analysis of composite plate-cavity systems via CUF finite elements. Compos Struct 259:113428. https://doi.org/10.1016/j.compstruct.2020.113428
Bank LC, Melehan TP (1989) Shear coefficients for multicelled thin-walled composite beams. Compos Struct 11:259–276. https://doi.org/10.1016/0263-8223(89)90091-3
Rychter Z (1987) On the shear coefficient in beam bending. Mech Res Commun 14:379–385. https://doi.org/10.1016/0093-6413(87)90059-0
Mindlin RD, Deresiewicz H (1954) Thickness-shear and flexural vibrations of a circular disk. J Appl Phys 25:1320–1332. https://doi.org/10.1063/1.1721554
Yildirim V, Kiral E (2000) Investigation of the rotary inertia and shear deformation effects on the out-of-plane bending and torsional natural frequencies of laminated plates. Compos Struct 49:313–320. https://doi.org/10.1016/S0263-8223(00)00063-5
Dong SB, Alpdogan C, Taciroglu E (2010) Much ado about shear correction factors in Timoshenko beam theory. Int J Solids Struct 47:1651–1665. https://doi.org/10.1016/j.ijsolstr.2010.02.018
Steinboeck A, Kugi A, Mang HA (2013) Energy-consistent shear coefficients for beams with circular cross sections and radially inhomogeneous materials. Int J Solids Struct 50:1859–1868. https://doi.org/10.1016/j.ijsolstr.2013.01.030
Cowper GR (1966) The shear coefficient in Timoshenko’s beam theory. J Appl Mech 33:335–340. https://doi.org/10.1115/1.3625046
Stephen NG (1980) Timoshenko’s shear coefficient from a beam subjected to gravity loading. J Appl Mech 47:121–127. https://doi.org/10.1115/1.3153589
Pai PF, Schulz MJ (1999) Shear correction factors and an energy-consistent beam theory. Int J Solids Struct 36:1523–1540. https://doi.org/10.1016/S0020-7683(98)00050-X
Hutchinson JR (2001) Shear coefficients for Timoshenko beam theory. J Appl Mech 68:87–92. https://doi.org/10.1115/1.1349417
Chan KT, Lai KF, Stephen NG, Young K (2011) A new method to determine the shear coefficient of Timoshenko beam theory. J Sound Vib 330:3488–3497. https://doi.org/10.1016/j.jsv.2011.02.012
Kennedy GJ, Hansen JS, Martins JRRA (2011) A Timoshenko beam theory with pressure corrections for layered orthotropic beams. Int J Solids Struct 48:2373–2382. https://doi.org/10.1016/j.ijsolstr.2011.04.009
Schramm U, Kitis L, Kang W, Pilkey WD (1994) On the shear deformation coefficient in beam theory. Finite Elem Anal Des 16:141–162. https://doi.org/10.1016/0168-874X(94)00008-5
Gruttmann F, Wagner W (2001) Shear correction factors in Timoshenko’s beam theory for arbitrary shaped cross-sections. Comput Mech 27:199–207. https://doi.org/10.1007/s004660100239
Elishakoff I (2020) Handbook of Timoshenko–Ehrenfest beam and Uflyand–Mindlin plate theories. World Scientific, Singapore
Engesser F (1981) Üer Knickfestigkeit gerader Stäbe. Z Arch Ing Vereins Hannover 35:733–744 (in German)
Föppl A (1987) Vorlesungen über Technische Mechanik-Dritter Band: Festigkeitslehre. B.G. Teubner, Leipzig (in German)
Iesan D (2009) Classical and generalized models of elastic rods. CRC series: modern mechanics and mathematics. CRC Press, Boca Raton
Faghidian SA (2016) Unified formulation of the stress field of Saint-Venant’s flexure problem for symmetric cross-sections. Int J Mech Sci 111–112:65–72. https://doi.org/10.1016/j.ijmecsci.2016.04.003
Faghidian SA (2020) Two-phase local/nonlocal gradient mechanics of elastic torsion. Math Methods Appl Sci. https://doi.org/10.1002/mma.6877
Faghidian SA, Żur KK, Reddy JN (2022) A mixed variational framework for higher-order unified gradient elasticity. Int J Eng Sci 170:103603. https://doi.org/10.1016/j.ijengsci.2021.103603
Faghidian SA, Żur KK, Pan E, Kim J (2022) On the analytical and meshless numerical approaches to mixture stress gradient functionally graded nano-bar in tension. Eng Anal Bound Elem 134:571–580. https://doi.org/10.1016/j.enganabound.2021.11.010
Żur KK, Faghidian SA (2021) Analytical and meshless numerical approaches to unified gradient elasticity theory. Eng Anal Bound Elem 130:238–248. https://doi.org/10.1016/j.enganabound.2021.05.022
Reddy JN (2017) Energy principles and variational methods in applied mechanics, 3rd edn. Wiley, New York
Renton JD (1991) Generalized beam theory applied to shear stiffness. Int J Solids Struct 27:1955–1967. https://doi.org/10.1016/0020-7683(91)90188-L
Faghidian SA (2017) Unified formulations of the shear coefficients in Timoshenko beam theory. J Eng Mech 143:06017013. https://doi.org/10.1061/(ASCE)EM.1943-7889.0001297
Timoshenko SP (1920) On the differential equation for the flexural vibrations of prismatic rods. Glas Hrvat Prir Druš 32:55–77
Kaneko T (1975) On Timoshenko’s correction for shear in vibrating beams. J Phys D: Appl Phys 8:1927–1939. https://doi.org/10.1088/0022-3727/8/16/003
Timoshenko SP (1922) On the buckling of deep beams. Letters to the editor. Philos Mag 43:1023–1024. https://doi.org/10.1080/14786442208633955
Kaneko T (1978) An experimental study of the Timoshenko’s shear coefficient for flexurally vibrating beams. J Phys D: Appl Phys 11:1979. https://doi.org/10.1088/0022-3727/11/14/010
Hutchinson JR (1981) Transverse vibrations of beams, exact versus approximate solutions. J Appl Mech 48:923–928. https://doi.org/10.1115/1.3157757
Wittrick WH (1987) Analytical, three-dimensional elasticity solutions of some plate problems, and some observations on Mindlin’s plate theory. Int J Solids Struct 23:441–464. https://doi.org/10.1016/0020-7683(87)90010-2
Stephen NG (1997) Mindlin plate theory: best shear coefficient and higher spectra validity. J Sound Vib 202:539–553. https://doi.org/10.1006/jsvi.1996.0885
Zhilin PA (2007) Applied mechanics: theory of thin elastic rods. St. Petersburg University Press, St. Petersburg (in Russian)
Mekhtiev MF (2018) Vibration of hollow elastic bodies. Springer, Berlin
Stephen NG, Levinson M (1979) A second order beam theory. J Sound Vib 67:293–305. https://doi.org/10.1016/0022-460X(79)90537-6
Stephen NG (2001) Discussion: shear coefficients for Timoshenko beam theory. J Appl Mech 68:959–960. https://doi.org/10.1115/1.1412454
Puchegger S, Bauer S, Loidl D, Kromp K, Peterlik H (2003) Experimental validation of the shear correction factor. J Sound Vib 261:177–184. https://doi.org/10.1016/S0022-460X(02)01181-1
Hutchinson JR (2001) Closure to on shear coefficients for Timoshenko beam theory. J Appl Mech 68:960–961. https://doi.org/10.1115/1.1412455
Faghidian SA (2018) On non-linear flexure of beams based on non-local elasticity theory. Int J Eng Sci 124:49–63. https://doi.org/10.1016/j.ijengsci.2017.12.002
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Faghidian, S.A., Elishakoff, I. The tale of shear coefficients in Timoshenko–Ehrenfest beam theory: 130 years of progress. Meccanica 58, 97–108 (2023). https://doi.org/10.1007/s11012-022-01618-1
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DOI: https://doi.org/10.1007/s11012-022-01618-1