From coupon to part
Chapters 4–5 used a flat coupon, one stack everywhere; a real part is curved and its stack changes from region to region (AddPly's spar: 16 plies, 2.144 mm on the web; rails add 4, root pads 2). A flat-coupon ABD is a local approximation, used patch by patch.
Predict · at 0:49 in the video
So is the flat coupon's stiffness exact for a curved part?
No. It's a local, flat approximation. Use it patch by patch: where the stack is constant, and the part is gently curved compared with its thickness.
This course is our own. These books go deeper.
- Basic Mechanics of Laminated Composite Plates, A. T. Nettles, NASA Reference Publication 1351, 1994
- Mechanics of Composite Materials, R. M. Jones, Taylor & Francis, 2nd ed., 1999
- Engineering Mechanics of Composite Materials, I. M. Daniel & O. Ishai, Oxford University Press, 2nd ed., 2006
- Design and Analysis of Composite Structures, C. Kassapoglou, Wiley, 2nd ed., 2013
- Composite Materials Handbook (CMH-17), Volume 3, Rev. G, CMH-17, SAE International, 2012
The course designs in AddPly, our browser app for laminate design: regions, ply stacks with live stacking-rule checks, thickness, mass and the ply book. It does not do strength, failure or draping; where a lesson covers those, the simulation is our own.
Simulations in this lesson are our own. Ply data come from the datasheet or textbook named on screen; where a number rests on an assumption, the video says so.
