Vertical Tie (CE):

The vertical tie or sag tie, CE, will be designed for a tensile force of

15,512 N.

The actual length being 2.5 m

As determined earlier σat allowed = 200 MPa

∴ Net area required = 15512/200 = 78 mm²

Selecting a 40 × 40 × 5 IS angle, Area = 3.78 cm²

Assuming 16 mm dia rivets,

Area of rivet hole = (16 +1.5) × 6 = 105 mm²

Area of attached leg = A¹ = 378/2 - 105 = 84 mm²

Area of outstanding leg A₂  =378/2          = 189 mm²

K =      3A₁/(3A₁  + A₂)

=          3 × 84/(3 × 84 + 189)= 0.57

∴ Net effective area = A₁ + k A₂

= 84 + 0.57 × 189 = 192 mm2 > 78 mm²    OK.