6-146 



DESIGN OF LAMINATES 



Case 1. All Edges Simply Supported 



Vn(n - 1) < 2 < Vn(n + l) n = 2 



l cr " 12 



£ + £ + 2k 

 n2 r 2 



9.8696 

 12 



jj + J + 2.3U58 



3.57 



(6. 52) 

 (6. 51) 



P = k 

 cr cr o 



12J5L5 = 3>5? x 12 x 10376 . 3#5? x 311#28 = m2 lWin< (6. 50) 



20-= 



Case 2. Loaded Edges Simply Supported - Remaining Edges Clamped 

 i /n(n - 1) /F < 2< i V n (n + 1)/J n = 3 



I;*' 



cr 



l! + 3nL + I 

 n 2 I6r2 2 



. U x 9.8696 



I' hnh * °- 5M < 



6.3739 



P cr = 6.3739 x 311.28 = 1985 lbs. /in. 



Case 3. Loaded Edges Clamped - Remaining Edges Simply Supported 



2 



(6. 52a) 



(6. 51a) 

 (6. 50) 



a ' k cr, = tB 



2 16 o 

 3r + ~o + 8 k 



5.23 



U.26 Controls 



5.0U 



- 6.3U 



P cr = U.26 x 311.28 = 1326 lbs ./in. 



(6. 51b) 

 (6. 51c) 



(6. 51d) 



(6. 51e) 

 (6. 50) 



Case 4. All Edges Clamped 



a * k cr x " 9 



b. k 



cr TEo 



c. k 



r, 13 



o 2 3_ 



3r + -o + 2k 

 r^ 



9 12 3 

 lbr^ + — x + U0k 

 r^ 



9 51 



2r^ + ^o + 10k 

 r^ 



16.56 

 7.36 

 7.12 Controls 



(6. 51f) 

 (6.51g) 

 (6.51h) 



