Introduction: Elementary theory of bending – Introduction to semi-Monocoque structures - Stresses in beams of symmetrical and unsymmetrical sections -Box beams – General formula for bending stresses- principal axes method – Neutral axis method.
Shear Flow: Shear stresses in beams – Shear flow in stiffened panels - Shear flow in thin walled open tubes – Shear centre – Shear flow in open sections with stiffeners.
Shear Flow Analyses: Shear flow in closed sections with stiffeners– Angle of twist - Shear flow in two flange and three flange box beams – Shear centre - Shear flow in thin walled closed tubes - Bredt-Batho theory - Torsional shear flow in multi cell tubes - Flexural shear flow in multi cell stiffened structures.
Failure concepts: Stability problems of thin walled structures– Buckling of sheets under compression, shear, bending and combined loads - Crippling stresses by Needham’s and Gerard’s methods–Sheet stiffener panels- Effective width, Inter rivet and sheet wrinkling failures-Tension field web beams(Wagner’s).
Launch Vehicle and Spacecraft Structures: Launch vehicle structures – Loads and stresses, thin walled pressure vessels, Buckling of beams, thin wall assumption. spacecraft - mini, micro structures, inflatable structures, flying effector, nanotubing.
Course Outcomes:
At the end of the course the student will be able to:
1. CO1: Compute the shear flow in open and closed section.
2. CO2: Analyze the stability problems of thin walled structures.
3. CO3: Distinguish the mini and micro structures.
Question paper pattern:
• The question paper will have ten full questions carrying equal marks.
• Each full question will be for 20 marks.
• There will be two full questions (with a maximum of four sub- questions) from each module.
• Each full question will have sub- question covering all the topics under a module.
• The students will have to answer five full questions, selecting one full question from each module.
Textbooks
1 Aircraft Structures for Engineering Students Megson, T.M.G ELSEVIER 5th edition,2013
2 Analysis and Design of Flight Vehicle Structures E.F. Bruhn Tristate Offset Co 1980
Reference Books
1 Aircraft Structures Peery, D.J. and Azar, J.J McGraw-Hill,New York 2nd Edition,1993
2 Theory of Plates and Shells Stephen P. Timoshenko & S.woinowsky Krieger McGraw-Hill, Singapore 2nd edition, 2010
3 Theory and Analysis of Flight structures Rivello, R.M McGraw-Hill, N.Y 1993