Slendness: k. L / r <= 300

Gross area
  The gross area A_g of a member at any point is the sum of the products of the thickness and the gross width of each element measured normal to the axis of the member.

Net Area
  Net area A_n 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:
    A_e = A_n . U

  U - reduction coefficient = 1 - x/L
  x - connection eccentricity
  L - length of the connection in the direction of loading

  Welds:
  (a) When the tension load is transmitted only by longitudinal welds to other than a plate member or by longitudinal welds in combination with transverse welds:
    A_e = A_g . U

  U - reduction coefficient = 1 - x/L
  A_g - gross area of member

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

  U = 1.0
  A - area of directly connected elements

  (c) When the tension load is transmitted to a plate only by longitudinal welds along both edges at the end of the plate:
    A_e = A_g . U

  A_g - gross area of member

  for L >= 2w ...........................U= 1.0
  for 2w > L >= 1.5w ..................U= 0.87
  for 1.5w > L >= w ..................U= 0.75

  L = length of weld
  w = plate width (distance between welds)

Design Strength for Tension:

  Tensile Yielding:
     P_n = F_y.A_g

     f_t = 0.9 (LRFD)
     O_t = 1.67 (ASD)
  Tensile Rupture:
     P_n = F_u. A_e

     f_t = 0.75 (LRFD)
     O_t = 2.0 (ASD)

Design Strength for Shear:

  Shear Yielding:
     R_n = 0.6 F_y. A_g

     f = 1.0 (LRFD)
     O = 1.5 (ASD)

  Shear Rupture:
     R_n = 0.6 F_u. A_nv

     f = 0.75 (LRFD)
     O = 2.0 (ASD)

  Block Shear Rupture Strength:

     R_n = 0.6 F_u.A_nv + U_bs. F_u.A_nt <= 0.6 F_y .A_gv + U_bs. F_u.A_nt

     f = 0.75 (LRFD)
     O = 2.0 (ASD)

    A_nt = net area subject to tension
    A_nv = net area subject to shear
    A_gv = gross area subject to shear
    U_bs = 1.0 when tension stress is uniform, U_bs = 0.5 when tension stress is non-uniform