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4 <br />Project As Built Koehler Tunnel Bulkhead By JFA Date 9/6/03 <br />8.42' x 10.5' (12.04' Thick, Sta 3+02) <br />Sheet 5 of 6 <br />Critical section shear strent=_th for 12-ft thick reinforced concrete deep-beam bendinE <br />stress desil=_n for earthquake acceleration: <br />Deep beam defined as Ud<5 (ACI 318-95, Sec 11.8.1). This is the case for earthquake acceleration of <br />0.136g and critical section shear at 0.151(1.275 ft) from ribside (ACI 318-95, Sec 11.8.5). <br />1•(12) = 0.719 < 5 Therefore, this is a deep beam for design! <br />a <br />v „ -nominal shear stress shall not be greater than 8 times sq rt of f ~ when Ud < 2 (ACI 318-95, <br />Sec 11.8.7) <br />Limiting values: v n := 8• 3000 v n = 438.2 psi <br />V n := v n•12-b u,•d V n = 738663 lb/ft, limiting shear force per foot of beam <br />width <br />Developed shear force at critical section: <br />V n := 0.35 •u•1 V ~ = 174707 ]b/ft, nominal shear force per foot of beam <br />width <br />V <br />V u :_ -° V u = 205538 Ib/ft, factored shear force per foot of beam width <br />0~ <br />Developed moment at critical section: <br />z <br />M ^ := 0.06375•u ~1) M n = 133969 ft-16, nominal critical bending moment per foot of <br />2 beam width <br />M <br />M u :_ -° M u = 148855 ft-Ib, factored critical bending moment per foot of beam <br />~' n r~idth <br />Permitted concrete shear strength (v ~): <br />Limiting value for v~ v o := 6 f c (ACI 318-95, Sec 11.8.7) <br />v e := 6 f e v e= 328.6 psi <br />Limiting value for term K = [3.5-2.5(M„N „d)] _ <br />2.5 2.5 •M u <br />K:=3.5- K=3.345 <br />V u•d <br />12 <br />Therefore, K := 2.5 <br />KhatAlcmN 911/190311:31 AM <br />