Design of Power driven shop rivets:

A roof truss tie member carries a tensile force of 250 kN. It is to be an IS angle member 1.2 m long and connected to a 10 mm gusset plate (f_y = 250 MPa).

Design the member using:

(a) Power driven shop rivets, and

(b) 5 mm fillet welds.

Solution

Case (a) : Using Riveted Connection

By Unwin's formula, rivet diameter = 6.01√10 = 19 mm (say 20 mm. dia rivets)

∴ Diameter of rivet hole = 20 + 1.5 = 21.5 mm

Value of rivet (R)

(i) In single shear

π/4 d² τ_vf  = π/4(21.5)²  × 100 = 36305 N

 (ii) In bearing = d ⋅ t σ _pt = 10 × 21.5 × 300 = 64305 N

∴ R adopted is 36305 N

Number of rivets required = 250000/36305 = 6.9 (say 7 rivets)

Permissible stress in steel = 0.6 f_y = 0.6 × 250 = 150 MPa

∴ Net area of member = 250000/150 = 1667 mm²

Add 30% for deductions,

Gross Area (A_g) = 1.3 × 1667 = 2168 mm²

∴ Provide =150 × 75 × 10 mm size (A_g = 2160 mm²)