Welded Joints v/s Riveted Joints:

Find the net effective area of an ISA 150 × 75 × 10 connected by its longer leg to a 12 mm gusset plate by 5 mm welds. Compare it with the net effective area of the same angle when connected by 20 mm dia rivets (single hole).

Solution

Welded Connection

Area of connected length (A₁) = (150 - (10 /2)) × 10 = 1450 mm²

Area of unconnected length (A₂) = (75 - 10/2)) × 10 = 700 mm²

Factor k =      3A₁/(3 A₁  + A₂) =    3 × 1450/(3 × 1450 + 700)= 0.8614

∴ Net effective area = A₁ + kA₂ = 1450 + 0.8614 × 700 = 2053 mm²

(a) Welded Connection

(b) Riveted Connection

Figure

Riveted Connection

Diameter of rivet hole = 20 + 1.5 = 21.5 mm

Area of connected leg, A₁ = (150 - 21.5 - (10/2) × 10 = 1235 mm²

Area of unconnected leg, A₂ = (75 - (10/ 2)) × 10 = 700 mm²

Factor, k = 3 × 1235/ (3 × 1235 + 700) = 0.8751

∴ Net effective area = A₁ + A₂ k = 1235 + 700 × 0.8751 = 1847 mm²