BOAT HULL DESIGN 2-49 



Deck area supported = 28 in. x 30 in. = 8h0 sq. in. 



Deck loading = 0.89 psi 



Shear load, V = 81j0 y °' 89 = 31h lbs. (2.24) 



Assume cloth laminate : 



Ultimate shear stress, F su = 9000 psi (Table 5-14) 



Allowable shear stress, f s = 9000 = 2250 psi (2.9) 



Area renuired = tlh. = 0.166 in. (2. 19a) 



2250 



Thickness of laminate faces, t = 



t = s2£* = .011, in. 

 2x6 



Area 

 2 x h 



Use 1 ply of cloth, t = .016 in. on each side. (Table 5-1) 



Add 1 ply of 1-1/2 oz. mat on each side for added 

 resistance to local impact and to improve the 

 core to face bond. 



Deck Edge Connecting Angle: This connection is required to carry the same ultimate 

 shear loading as the deck laminate. 



Reinforcement woven roving for high impact resistance. 



Deck Laminate: 1 ply cloth, 2 plies 2 ounce mat and 1 ply woven roving. 



Ultimate shear strength per running in. : 



F 'su " A clFscl + AmF sm + A >rr F swr ( 2 . 30 ) 



Where A = area 



F' su = ultimate shear strength, lbs. ::er in. (Table 5-14) 



cl,m,wr = subscripts referring to cloth, mat, and 

 woven roving respectively 



F = F x G °-T? * '$ 2 x 1Qi - v v i u (2 31) 



^sc ^swr x ~ — " F swr x ~- r " F S wr x 1 * 16 V ' 



°wr ,h$ x 10° 



f = f c x ^L = f v - h0 x lp6 =f * o 89 (? sn 



r sm 1 swr r swr ~rz T r swr x u,uy \a. 61) 



G wr -U5 x 10° 



G = shear modulus, psi (Table 5-14) 



Ultimate shear strength, F 1 gu = (1 x .016) 7500 x 1.16 + 



(1 x .116) 7500 x .89 + (1 x .037) 7500 = 139 + 775 + 278 

 = 1192 lbs. per in. 



