PROFIS ENGINEERING
CASE 1 / CASE 2 applies for row 1 and row 3: calculate V cbg from row 3 using c a1, row 3.
V b = 7 l e d a
0.2 d a λ a f ′ c c a1
1.5
Reference yellow shaded area.
ACI 318-19 Eq.( 17.7.2.2.1a)
l e = MIN h e f | 8d a = 6.0 in h ef = 14.0 in d a = 0.75 in
normal weight concrete: λ = 1.0 → λ a = 1.0 ACI 318-19 Table 17.2.4.1
V b = [( 7)( 6.0 in / 0.75 in) 0. 2( 0.75 in) 0. 5 ]( 1.0)( 3500 psi) 0. 5( 18.0 in) 1. 5
= 41,513 lb V b = 9λ a f ′ c c a1
1.5 f’ c = 3500 psi
ACI 318-19 Eq.( 17.7.2.2.1b)
c a1, row 3 = 18.0 in
V b =( 9)( 1.0)( 3500 psi) 0. 5( 18.0 in) 1. 5 = 40,662 lb f’ c = 3500 psi c a1, row 3 = 18.0 in check: design V b = MIN { 41,513 lb; 40,662 lb } = 40,662 lb ACI 318-19 17.7.2.2
8d a = 6.0 in CONTROLS
V cbg =
A Vc A Vc0 ψ ec, V ψ ed, V ψ c, V ψ h, V ψ parallel, V V b
V cbg, row 3 =( 1248 in 2 / 1458 in 2)( 0.939)( 1.0)( 1.0)( 1.3)( 1.0)( 40,662 lb)
= 42,487 lb
A Vc = 1248 in 2 |
A Vc0 = 1458 in 2 |
ψ ec, V = 0.939 |
ψ ed, V = 1.0 |
ψ c, V = 1.0 |
ψ h, V = 1.3 |
ψ parallel, V = 1.0 |
V b = 40,662 lb |
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