Flexural-Torsional Vibrations of Rotating Tapered Thin Walled Composite Box Beam

Thin-walled composite box beam structural configuration is representative of a specific high aspect ratio wing structure. The optimal design procedure and lay-up definition including appropriate coupling necessary for aerospace applications has been identified by means of “ad hoc” analytical formulation and by application of commercial code. The overall equivalent bending, torsional and coupled stiffness are derived and the accuracy of the simplified beam model is demonstrated by the application of Altair Optistruct. A simple case of a coupled cantilevered beam with load at one end is introduced to demonstrate that stiffness and torsion angle distribution does not always correspond to the trends that one would intuitively expect. The maximum of torsional stiffness is not obtained with fibers arranged at 45° and, at the maximum torsional stiffness, there is no minimum rotation angle. This observation becomes essential in any design process of composite structures where the constraints impose structural couplings. Furthermore, the presented theory is also extended to cases in which it is necessary to include composite/stiffened hybrid configurations. Good agreement has been found between the theoretical simplified beam model and numerical analysis. Finally, the selected composite configuration was compared to an experimental test case. The numerical and experimental validation is presented and discussed. A good correlation was found confirming the validity of the overall optimization for the optimal lay-up selection and structural configuration.

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Static Response of Thin-Walled CNT-Reinforced-Laminated Composite Box Beam

Lecture Notes in Civil Engineering - Recent Advances in Structural Engineering, Volume 2 ◽

10.1007/978-981-13-0365-4_61 ◽

2018 ◽

pp. 723-734

Author(s):

Tushar Sharma ◽

V. Murari ◽

K. K. Shukla

Keyword(s):

Laminated Composite ◽

Static Response ◽

Box Beam ◽

Thin Walled ◽

Composite Box Beam

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A new 3-D element formulation on displacement of steel-concrete composite box beam

Journal of Central South University ◽

10.1007/s11771-013-1622-8 ◽

2013 ◽

Vol 20 (5) ◽

pp. 1354-1360 ◽

Cited By ~ 3

Author(s):

Ling-yu Zhou ◽

Zhi-wu Yu ◽

Gui-chao He

Keyword(s):

Element Formulation ◽

Box Beam ◽

Composite Box Beam

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Computer analysis of thin-walled concrete box beams

Canadian Journal of Civil Engineering ◽

10.1139/l89-133 ◽

1989 ◽

Vol 16 (6) ◽

pp. 902-909 ◽

Cited By ~ 6

Author(s):

Shahbaz Mavaddat ◽

M. Saeed Mirza

Keyword(s):

Key Words ◽

Computer Analysis ◽

Shear Stresses ◽

Shear Lag ◽

Applied Loading ◽

Box Beam ◽

Box Beams ◽

Three Stages ◽

Thin Walled ◽

Normal And Shear Stresses

Three computer programs, written in FORTRAN WATFIV, are developed to analyze straight, monolithically cast, symmetric concrete box beams with one, two, or three cells and side cantilevers over a simple span or over two spans with symmetric mid-span loadings. The analysis, based on Maisel's formulation, is performed in three stages. First, the structure is idealized as a beam and the normal and shear stresses are calculated using the simple bending theory and St-Venant's theory of torsion. The secondary stresses arising from torsional and distortional warping and shear lag are calculated in the second and third stages, respectively. The execution times on an AMDAHL 580 system are 0.02, 0.93, and 0.25 s for the three programs, respectively. The stresses arising in each stage of analysis are then superposed to determine the overall response of the box section to the applied loading. The results are compared with Maisel's hand calculations. Key words: bending, bimoment, box beam, computer analysis, FORTRAN, shear, shear lag, thin-walled section, torsion, torsional and distortional warping.

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