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Project Design Mogul Tunnel Bulkhead By JFA Date T/4/03 <br />8' x 8' (9' Thick. Station 2+41) <br />Sheet 5 of 6 <br />Critical section shear strength for 9-ft thick reinforced concrete deep-beam bending <br />stress design for earthquake acceleration: <br />Deep beam defined as lld<5 (ACI 318-95, Sec 11.8.1}. This is the case for earthquake acceleration of <br />0.094g and critical section shear at 0.151(120 ft) from ribside (ACI 318-95, Sec 11.8.5). <br />1 (12) = 0.919 < 5 Therefore, this is a deep beam for design! <br />d <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 W~d V n = 549475 Ib/ft, limiting sheaz force per foot ofbeam <br />width <br />Developed shear force at critical section: <br />V n := 035 ~u l V n = 66145 Ib/ft, nominal shear force per foot ofbeam <br />width <br />v <br />V u :_ ° V u = 77818 lb/ft, factored shear force per foot ofbeam width <br />~ rs <br />Developed moment at critical section: <br />z <br />M n := 0.06375 ~ ~ ~ l~ M n = 48192 ft-Ib, nominal critical bending moment per foot of <br />2 beam width <br />M <br />M ~~ :_ -n M ^ = 53546 ft-Ib, factored critical bending moment per foot ofbeam <br />.~ lLliiii~ <br />Permitted concrete shear strength (v ~): <br />Limiting value for v~ v e := 6 f c <br />(ACI 318-95, Sec 11.8.7) <br />ve:=6 fc ve=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=3.302 <br />V u•d <br />12 <br />Therefore, K := 2.5 <br />~ami.,,Ka uiu~vos izza eM <br />