V mbg = A Vm A Vmo ψ ec, V, m ψ ed, V, m Ψ m, V ψ h, V, m ψ parallel, V, m V b, m
V mbg =
43 in. 2 1. 0 1. 0 1. 4 1. 0 1. 0 940 lbs
22 in. 2 V mbg = 2, 572 lbs
Masonry pryout failure— Nominal strength
V mpg = k cp MIN N mbg; N mag V mpg = 2.0 MIN 4, 737 lbs; 9, 106 lbs V mpg = 9, 474 lbs
Masonry crushing failure— Nominal strength
V mc = 1750 4 f ′ m A se, V
4 V mc = 1750 1, 500 psi 0.1419 in. 2))
V mc = 6, 684 lbs
A
vm = 2 1.5c a1 + 1.5c a1 MIN h; 1.5c a1 A Vm = 2 6. 563 in. MIN 7.625 in.; 3. 281in. A Vm = 43 in. 2
A Vmo = 4.5 × c a1
2 2
A Vmo = 4.5 × 2. 187 in. A Vmo = 22 in. 2 ψ ec, v, m = 1.0( No Eccentricity Present) ψ ed, v, m = 1.0( Since c a2 ≥ 1.5c a1) ψ m, V = 1.4( Uncracked Masonry) ψ h, V, m = 1.0( Since h a ≥ 1.5c a1)
ψ parallel, V, m = 1.0( Since Shear Load is Perpendicular to Hollow Head Joint Edge)
Masonry breakout failure— Nominal strength
V b, m = MIN V b, m1; V b, m2
V b, m1 = 7 MIN 8d a; h ef d a
0.2
V b, m1 = 7 d a f ′ m c a1
1.5
4 in. 0.2 1.5 0. 5 in. 1, 500 psi 2. 187 in.
0.5 in. V b, m1 = 940 lbs
V b, m2 = 9 f ′ m c a1
1.5 = 9 1, 500 psi 2. 187 in. 1.5
Shear utilization percentage
V ua ϕ steel V sa
=
V ua ϕ masonry V mbg
=
V ua ϕ masonry V mpg
=
V ua ϕ crushing V mc
=
250 lbs 0.65 4, 938 lbs = 7. 79 %
500 lbs 0.70 2, 572 lbs
= 27. 77 %
500 lbs 0.70 9, 474 lbs = 7. 54 %
250 lbs 0.50 6, 684 lbs = 7. 48 %
Tension and shear interaction
Tri-linear equation
Parabolic equation
N ua ϕN n
+
V ua ϕV n
≤ 1.2 500 lbs 500 lbs +
3, 079 lbs 1, 800 lbs ≤ 1. 2 0. 44 ≤ 1.2
N ua 5 / 3
+ V ua
5 / 3 ≤ 1.2 ϕN n ϕV n
500 lbs 3, 079 lbs
5 / 3 +
500 lbs 1, 800 lbs
5 / 3 ≤ 1. 2
0. 17 ≤ 1.0
V b, m2 = 1, 127 lbs V b, m = MIN 940 lbs; 1, 127 lbs = 940 lbs
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