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<br />D.) Maximum Horizontal Span ofUnreinforced Masonry: <br /> <br />Continuous across supports, M = W x L ^2 I 12 <br /> <br />Ft horiz = <br />Ft ' horiz = <br /> <br />50 psi <br />66.65 psi <br /> <br />(ACI 530, 5.3.2) <br /> <br />M=GCpxVpL^2/12 =Ft'hxSy <br /> <br />Sy= <br /> <br />81 <br /> <br />ci I Lf <br /> <br />(NCMA TEK 141A) <br /> <br />14.6 1ft <br /> <br />Therefore, L = (F't x Sy I (GCp x Vp) = <br /> <br />E.) Maximum Capacity of Reinforced Masonry Wall: <br /> <br />Compression flange width = <br /> <br />48 <br /> <br />In <br /> <br />(ACI 530, 7.3.2.1) <br /> <br />Rho = AsI bd = 0.00161 <br />Rho x N = 0.01951 <br /> <br />Therefore,k= 0.17898 andkxd= 0.71594 In <br />Since k x d is < 1.25", treat as a soild block. <br /> <br />j = 0.94034 <br /> <br />Masonry Capacity: <br /> <br />Mm = 1/2 (Fm x j x k x b x d^2) <br /> <br />Mm= <br /> <br />116,333 in -lbs <br /> <br />Reinforcing Steel Capacity: <br /> <br />Fs = 20,000 pSI <br />fa = (Wall + Bond Bm. Dead Load) x b I As = 5591 pSI <br /> <br />(ACI 530, 7,2) <br /> <br />Fs' = 1.333 x Fs + fa (compressive stress) = 32,191 pSI <br /> <br />Ms = As X Fs' xj x d = 37,536 in-Ibs <br /> <br />Therefore, reinforcing steel stress governs. <br /> <br />Therefore, L = 12 x Ms I GCp x Vp x H^2 = I 23.3 1ft <br /> <br />Page 11 <br /> <br /> <br />. <br />s Catalano, P. E. <br />8/ l/95 <br />