Question

What is the strength of weld  per mm length used to connect two plates of 10mm thickness using a lap joint?

(a) 795.36 N/mm

(b) 295.5N/mm

(c) 552.6 N/mm

(d) 487.93 N/mm

I got this question in an international level competition.

This is a very interesting question from Design of Welds topic in division Welded Connections of Design of Steel Structures

Answer 1

The correct choice is (a) 795.36 N/mm

Easy explanation: Minimum size of weld = 3mm

Maximum size of weld = 10-1.5 = 8.5mm

Assume weld size = 6mm

Effective throat thickness, te = 0.7 x 6 = 4.2mm

Strength of weld = te [fu/(√3 x 1.25)] = 410 x 4.2 /(√3 x 1.25) = 795.36 N/mm.