2-44 BOAT HULL DESIGN 



From Fig. 6-32, Type B laminate with 2 plies of 1-1/2 ounce mat. 

 Framing: 



Spacing = 19 in. 

 Length = 31 in. 



Load per inch = 0.69 x 19 = 16. '1 lbs. per in. 



^ PL 2 . 16.91 (31) 2 



bending moment, M 



12 



12 



135U in. -lbs. (2. 21) 

 (2. 22) 



Required Section Modulus, Z = Tptjgg = «3U3 in. 3 



From Fig. 6-37, use 1 in. x 4 in. stiff ener with 2 plies of woven roving. 



The deflection of the Fore Deck is not checked since it is not a normal walking area in 

 a boat this size. 



Cockpit Deck: 



i 



"1 



Fig. 2-23. Cockpit deck sand- 

 wich cross-section 



Design Load = U0 psf = 0.28 psi 



Maximum Span = 8 in. 



Construction - Use sandwich construction for lightness and rigidity, 



Try a l/U inch thick core with one ply of woven roving on each face. 



For 1 in. strip bending moment: 



M 



= pLf = 0.28 x (8) : 



= 1.U9 in. -lbs. 



12 12 



The dimensions for the cross section indicated in Fig. 2-23 are 



b = 1 in. 



h-L = 0.25 in. 



h = 0.25 + 0.07U = 0.32U in. 



(2.21) 



