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Axial Tension
Maximum Size of Bolt Holes
 Nominal Bolt Diameter (in.) Standard Hole Diameter (in.), Oversize Hole Diameter (in.) Short-Slotted Hole (in.) Long-Slotted Hole (in.) d < 1/2 d + 1/32 d + 1/16 (d + 1/32) by (d + 1/4) (d + 1/32) by (2.5d) d ≥ 1/2 d + 1/16 d + 1/8 (d + 1/16) by (d + 1/4) (d + 1/16) by (2.5d)
Tension Member Design

Gross area
Ag = Gross area of cross section.

Net Area
Net area An of a member is the sum of the products of the thickness and the net width of each element.
For a part in any diagonal or zigzag line, the additional quantity is:   s2.t / (4g)

s = longitudinal center-to-center spacing (pitch) of any two consecutive holes.
g = transverse center-to-center spacing (gage) between fastner gage lines.

Effective Net Area, Reduction-Shear Lag Coefficient (U)

Bolts:
Ae = An . U

For angle members having two and more bolts in the line of force:    U = 1 - 1.2 x/L < 0.9,   but >= 0.4

For channel members having two and more bolts in the line of force:    U = 1 - 0.36 x/L < 0.9,   but >= 0.5

x - distance from shear plane to centroid of the cross section

Welds:
(a) When the tension load is transmitted only by longitudinal welds or by longitudinal welds in combination with transverse welds:
Ae = Ag . U

U - reduction coefficient = 1 - x/L <= 0.9
Ag - gross area of member

(b) When the tension load is transmitted only by transverse welds:
Ae = A . U

U = 1.0
A - area of directly connected elements

(c) Otherwise:

for angle members:    U = 1 - 1.2 X/L < 0.9 but U >= 0.4

for channel members:    U = 1 - 0.36 X/L < 0.9 but U >= 0.5

x - distance from shear plane to centroid of cross section
L - length of longitudinal weld

Design Strength for Tension Members:

Yielding in the gross section: (Eq. C2-1)
fTn = f.Fy.Ag= 0.90 Fy.Ag   LRFD

Ta = Fy.Ag / Ot = Fy.Ag/1.67  ASD

Fracture in the net section: (Eq. C2-2)
fTn = f.Fu.Ae= 0.75 Fu.Ae  LRFD

Ta = Fu.Ae / Ot = Fu.Ae/2.0  ASD

Design Rupture Strength:

Shear Rupture Strength: (Eq. E5.1-1)
fVn = f(0.6).Fu.Anv= 0.75 (0.6) Fu.Anv  LRFD

Va = (0.6).Fu.Anv / O = (0.6) Fu.Anv/2.0   ASD

Tension Rupture Strength for Welded Connection: (Eq. E2.7-1)
fPn = f.Fu.Ae= 0.6 Fu.Ae  LRFD

Pa = Fu.Ae / O = Fu.Ae/2.5  ASD

Tension Rupture Strength for Bolted Connection: (Appendix A, E3.2)

a) For flat sheet connections not having staggered hole patterns:

1)   for washers are provided under both the bolt head and the nut
fPn = f. Ft. An   LRFD
Pa = Ft. An / O   ASD
for single bolt, Ft =(0.1 + 3d/s)Fu <= Fu
for multiple bolts, Ft = Fu
f = 0.65 for double shear, 0.55 for single shear

O = 2.0 for double shear, 2.22 for single shear

2)   for washers are NOT provided under both the bolt head and the nut

fPn = f. Ft. An   LRFD
Pa = Ft. An / O   ASD
for single bolt, Ft = (2.5 d/s)Fu <= Fu
for multiple bolts, Ft = Fu
f = 0.65

O = 2.0

b) For flat sheet connections having staggered hole patterns:

fPn = f. Fu.An
f = 0.65   LRFD

Pa = Fu.An/ O
O = 2.22   ASD

c) For other than flat sheet:

fPn = f. Fu.(An.U)
f = 0.65   LRFD

Pa = Fu.(An.U) / O
O = 2.22   LRFD

d - nominal bolt diameter
s - sheet width divided by number of bolt holes in cross section

Block Shear Rupture Strength: (Eq. E5.3-1, E5.3-2)
The lesser of following:

LRFD
fRn = f [0.6 Fy.Agv + Fu.Ant]
fRn = f [0.6 Fu.Anv + Fu.Ant]

ASD
Ra = [0.6 Fy.Agv + Fu.Ant]/ O
Ra = [0.6 Fu.Anv + Fu.Ant]/ O

f = 0.65 for bolted connections, 0.6 for welded connections
O = 2.22 for bolted connections, 2.5 for welded connections

Ant = net area subject to tension
Anv = net area subject to shear
Agv = gross area subject to shear Reference: AISI S100-2007

Combined Bending and Tension C5.1.2

ASD
1).        Ob .Mx / Mnxt + Ob .My / Mnyt + Ot .T / Tn < = 1.0

2).        Ob .Mx /Mnx + Ob .My / Mny - Ot .T / Tn < = 1.0
LRFD
1).        Mux / (fb .Mnxt)+ Muy / (fb .Mnyt) + Tu / (ft. Tn) < = 1.0

2).        Mux / (fb .Mnx)+ Muy / (fb .Mny) - Tf / (ft. Tn) < = 1.0

Mx - Required allowable flexural strength about axis X
My - Required allowable flexural strength about axis Y
T - Required allowable axial strength

Ob = 1.67
Ot = 1.67

Mux - Required flexural strength about axis X
Muy - Required flexural strength about axis Y
Tu - Required axial strength

Mnxt = Sftx . Fy - Nominal flexural strength about axis X
Mnyt = Sfty . Fy - Nominal flexural strength about axis Y
Sftx - Section modulus of full unreduced section relative to extreme tension fibre about axis X
Sfty - Section modulus of full unreduced section relative to extreme tension fibre about axis Y

Mnx - Nominal flexural strength about axis X
Mny - Nominal flexural strength about axis Y
Tn - Nominal tensile strength

fb = 0.9 - resistance factor for bending
ft = 0.95 - resistance factor for shear