PROFIS ENGINEERING
N ag =
A Na A Na0 ψ ec, Na ψ ed, Na ψ cp, Na N ba ACI 318-19 Eq.( 17.6.5.1b)
c Na = 10d a τ uncr 1100
design τ k, uncr =( ESR τ k, uncr)( f ' c / 2500 psi) 0. 1 =( 2220 psi)( 3500 psi / 2500 psi) 0. 1 = 2296 psi c Na =( 10)( 0.75 in)( 2296 psi / 1100 psi) 0. 5 = 10.84 in
A Na =( c x- + s x12 + s x23 + s x34 + c x +)( c y- + s y12 + s y23 + s x34 + c y +) =( 10.84 + 4.0 + 4.0 + 16.0 + 10.84)( 6.0 + 4.0 + 8.0 + 8.0 + 10.84) = 1682.85 in 2 c x- = ∞ in = c Na
ACI 318-19 Eq.( 17.6.5.1.2b) Reference ESR-4868 Table 15 for τ k, uncr and() xx. ESR τ k, uncr = 2220 psi d a = 0.75 in() xx = 0.10 f’ c = 3500 psi
ACI 318-19 Fig. R17.6.5.1( b) c x + = ∞ in = c Na c y- = 6 in
s x12 = 4 in s x23 = 4 in s x34 = 16 in s y12 = 4 in s y23 = 8 in s y34 = 8 in
A Na0 =( 2c Na) 2 =( 21.68 in) 2 = 470.02 in 2 ACI 318-19 Eq.( 17.6.5.1.2a)
ψ ec, Na =
1 1 + e ′ N c Na c Na = 10.84 in ACI 318-19 Eq.( 17.6.5.3.1)
2c Na = 21.68 in
c y + = ∞ in = c Na ecc.( x direction): ψ ec1, N = 0.783 ecc.( y direction): ψ ec2, N = 0.916 x direction: e c1, N = 3.0 in c Na = 10.84 in y direction: e c2, N = 1.0 in ψ ec, N =( ψ ec1, N)( ψ ec2, N) =( 0.783)( 0.916) = 0.717
ψ ed, Na = 0.7 + 0.3 c a, min c Na
= 0.7 +( 0.3)( 6.0 in / 10.84 in) = 0.866
Reference ACI 318-19 Eq.( 17.6.5.4.1b)
c a, min = c y- = 6.0 in c Na = 10.84 in ψ cp, Na = MAX c a, min | c Na
= 1.0 cracked concrete Reference ACI 318-19 Eq.( 17.6.5.5.1b) c ac c ac
N ba = λ a α N, seis τ xxxx πd a h e f
ACI 318-19 Eq.( 17.6.5.2.1)
Reference ESR-4868 Table 15 for α N, seis. normal weight concrete: λ = 1.0 → λ a = 1.0 ACI 318-19 Table 17.2.4.1 design τ k, cr =( ESR τ k, cr)( f ' c / 2500 psi) 0. 1 =( 1260 psi)( 3500 psi / 2500 psi) 0. 1 = 1303 psi
Reference ESR-4868 Table 15 for τ k, cr and() xx. ESR τ k, cr = 1260 psi f ' c = 3500 psi() xx = 0.1
N ba =( 1.0)( 1.0)( 1303 psi)( π)( 0.75 in)( 14.0 in) = 42,982 lb d a = 0.75 in α N, seis = 1.0 h ef = 14.0 in
N ag =
A Na A Na0 ψ ec, Na ψ ed, Na ψ cp, Na N ba
N ag =( 1682.85 / 470.02)( 0.717)( 0.866)( 1.0)( 42,982) = 95,554 lb
Table 26. Nominal Steel Strength in Shear( V sa)
A Na = 1682.85 in 2 A Na0 = 470.02 in 2 ψ ec, Na = 0.717 ψ ed, Na = 0.866 ψ cp, Na = 1.0 N ba = 42,982 lb
V sa = 11,640 lb / anchor
Reference ESR-4868 Table 11 for V sa-value. Reference ESR-4868 Table 11 for α V, seis = N / A.
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