JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

UNIT - I

Thin Plate Theory, Structural Instability: Analysis of thin rectangular plates subject to bending, twisting, distributed transverse load, combined bending and in-plane loading- thin plates having small initial curvature, energy methods of analysis. Buckling of thin plates- elastic, inelastic, experimental determination of critical load for a flat plate, local instability, Tension field beams- complete diagonal tension, incomplete diagonal tension.

UNIT - II

Bending, Shear and Torsion of Thin Walled Beams: Unsymmetrical bending- resolution of bending moments, direct stress distribution, position of neutral axis. Deflections due to bending- approximations for thin walled sections, temperature effects. Shear loaded thin walled beams- general stress, strain and displacement relationships- direct stress - shear centre, twist and warping. Torsion of beams of closed section- displacements associated with Bredt-Batho shear flow. Torsion of open section beams. Warping of cross section- conditions for zero warping. Bending, shear, torsion of combined open and closed section beams.

UNIT - III

Structural Idealisation of Thin Walled Beams: Structural idealization- principal assumptions, idealization of panel, effect on the analysis of thin walled beams under bending, shear, torsion loading- application to determining deflection.

UNIT - IV

Structural and Loading Discontinuities in Thin Walled Beams: Closed section beams- shear stress distribution of a closed section beam built in at one end under bending, shear and torsion loads. Open section beams- I section beam subjected to torsion, torsion of beam of arbitrary section, torsion bending constant, distributed torque loading- extension of theory for general systems of loading. Shear lag- effect of shearing strains in beams- redistribution of bending stresses due to restraining of warping, limitation of elementary bending theory, effect of accounting for shear lag on the estimated strength.

UNIT - V

Stress Analysis of Aircraft Components- Wing, Fuselage: Wing spars and box beams- tapered wing spar, open and closed section beams, beams having variable stringer areas. Wings- Three-boom shell in bending, torsion, shear, tapered wings, deflections, cut-outs in wings. Bending, shear, torsion, cut-outs in fuselages. Fuselage frames and wing ribs- principles of stiffener/ web construction, fuselage frames, wing ribs.

R16 B.TECH AERONAUTICAL ENGG.

TEXT BOOKS:

• 1. Megson, T.H.G., Aircraft Structures for Engineering Students, 4th edn., Elsevier, 2007, ISBN 0-750-667397.
• 2. Peery, D.J. and Azar, J.J., Aircraft Structures, 2 nd edn., McGra-Hill, 1982, ISBN 0-07- 049196-8.

REFERENCES:

• 1. Allen, D.H. and Haisler, W.E., Introduction to Aerospace Structural Analysis, John Wiley, 2010.
• 2. Bruhn. E.H, Analysis and Design of Flight Vehicles Structures, Tri-state Off-set Company, USA, 1965.
• 3. Lakshmi Narasaiah, G., Aircraft Structures, BS Publications, 2010.
• 4. Sechler.E.E. and Dunn, L.G., Airplane Structural Analysis and Design, John Wiley & Sons, 1942 R16 B.TECH AERONAUTICAL ENGG.