PROFIS ENGINEERING
Nominal Bond Strength in Tension( N ag)
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)( 5000 psi / 2500 psi) 0. 1 = 2379 psi c Na =( 10)( 0.75 in)( 2379 psi / 1100 psi) 0. 5 = 11.03 in
A Na =( c x- + s x1 + s x2 + s x3 + c x +)( c y- + s y12 + s y23 + s x34 + c y +) =( 11.03 + 9.0 + 9.0 + 9.0 + 11.03)( 6.0 + 4.0 + 8.0 + 8.0 + 11.03) = 1816.69 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 = 5000 psi
ACI 318-19 Fig. R17.6.5.1( b) c x + = ∞ in = c Na c y- = 6 in
s x1 = 9 in s x2 = 9 in s x3 = 9 in s y12 = 4 in s y23 = 8 in s y34 = 8 in
A Na0 =( 2c Na) 2 =( 22.06 in) 2 = 486.64 in 2 ACI 318-19 Eq.( 17.6.5.1.2a)
ψ ec, Na =
1 1 + e ′ N c Na
= 0.917 eccentricity in y direction c Na = 11.03 in 2c Na = 22.06 in
ACI 318-19 Eq.( 17.6.5.3.1) e’ N = 1.0 in c Na = 11.03 in c y + = ∞ in = c Na ψ ed, Na = 0.7 + 0.3 c a, min c Na
= 0.7 +( 0.3)( 6.0 in / 11.03 in) = 0.863
Reference ACI 318-19 Eq.( 17.6.5.4.1b) c a, min = c y- = 6.0 in c Na = 11.03 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. 15 =( 1260 psi)( 5000 psi / 2500 psi) 0. 1 = 1350 psi
Reference ESR-4868 Table 15 for τ k, cr and() xx. ESR τ k, cr = 1260 psi f ' c = 5000 psi() xx = 0.1
N ba =( 1.0)( 1.0)( 1350 psi)( π)( 0.75 in)( 10.0 in) = 31,809 lb d a = 0.75 in α N, seis = 1.0 h ef = 10.0 in
N ag =
A Na A Na0 ψ ec, Na ψ ed, Na ψ cp, Na N ba
N ag =( 1816.69 in 2 / 486.64 in 2)( 0.917)( 0.863)( 1.0)( 31,809 lb) = 93,973 lb
A Na = 1816.69 in 2 A Na0 = 486.64 in 2 ψ ec, Na = 0.917 ψ ed, Na = 0.863 ψ cp, Na = 1.0 N ba = 31,809 lb
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