dhaunch = 7.00" (177.8mm)
tf = 0.420" (10.7mm)
0.8(1.5(1,557"k ))
= 91.1k (405.2KN)
∴ Ru =
13.91"+ 7.00"- 0.42"
Determine Capacity;
(R v ) W14X34 = 158k (702.8KN)
(calculated
previously)
Check;
φv R v = 0.75(158k ) = 119 k > 91.1k = R u (529.3KN > 405.2KN)
O.K.
Check panel-zone thickness;
t ≥ (d z + w z ) / 90
(EQ. 9-2 AISC Seismic provisions)
dz = 13.91"+7.00"-2(0.42") = 20.1" (510.5mm)
wz = dc-2tf = 13.98"-2(0.455") = 13.1" (332.7mm)
20.1"+ 13.1" d z + w z
∴ t = 0.285" < 0.369" =
=
N.G.
(7.24mm < 9.37mm)
90
90
Try a 3/8" (9.53mm) thick doubler plate (using ASTM A36);
Provide weld to match shear strength of the required thickness of doubler plate (use E70XX electrode);
Shear capacity of doubler plate = φ BM A g = φ BM t d b d
F
F
where; FBM = nominal shear capacity of base metal = 0.6Fy
Ag = gross area of the doubler plate
td = thickness of doubler plate
bd = width of doubler plate
Shear capacity of welds = φ w (0.707s)b d
F
Where; FW = nominal shear capacity of welds = 0.6FEXX
s = weld leg length
φ BM t d b d = φ W (0.707s)b d
Therefore;
F
F
φ BM t d
F
0.9(0.6(36ksi))0.369"
s=
=
= 0.322" (8.18mm)
or
0.707(φ W )
F
0.707(31.5ksi)
From AISC J2.2b, the maximum weld size is;
1" 3" 1"
s = td -
=-
= 0.313" (7.95mm)
N.G.
16 8 16
Try a 1/2" (12.7mm) thick doubler plate with a 3/8" (9.53mm) weld;
O.K.
For a 1/2" (12.7mm) thick doubler plate;
s = 0.438" (11.13mm)
O.K.
From AISC table J2.4, the minimum weld size is;
s = 3/16" < 3/8" (4.76mm < 9.53mm)
H4-51
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