Structural Engineering & Statics
where the load goes
Generator

The weld-group generator

Rendered here at the parameters it defaults to, with every essay that calls it — which is the same list as the blast radius of changing it.
Throat stress round a fillet weld groupA c shape weld group carrying 100 kN at 150 mm from its centroid. The peak throat stress is 0.88 kN per mm of throat, at (79.5, -100); the worst point at maximum radius from the centroid carries 0.88. Checking by radius is right here, and points at identical radius differ by a factor of 1.100 kNpeak 0.88Two points at maximum radiusthe radius rule finds the peak hereequal radius, stresses differ ×1

3 essays call weld-group. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the one its essay argues about.

Where it is called

Changing this generator changes every one of these figures.

100 kNe = 150centroidworst bolt 50.37 kNSix bolts · direct shear 16.67 kN eachelastic vector method Connections

The bolt that carries more than its share

Six bolts, one hundred kilonewtons, and a worst bolt carrying fifty. The load is shared equally and the torque is not, and the second one is invisible on any drawing where the connection is a point.

 0102030405060708090020406080100120140160angle between the weld and the load, degreescapacity, kN0° · 116.83 kN45° · 127.98 kN90° · 143.09 kN×1.22along Connections

The weld that is stronger across than along

The same fillet weld, the same size, the same steel, carries twenty-two per cent more when the load runs across it than along it. The factor is exactly the square root of three over the square root of two, and it comes out of the yield criterion rather than out of a test.

 100 kNpeak 0.88Two points at maximum radiusthe radius rule finds the peak hereequal radius, stresses differ ×1 Connections

The corner that is not the worst point

Check the point furthest from the centroid. It is the standard rule for a weld group under an eccentric load, it is exactly right for some shapes, and for others it misses the peak by sixteen per cent — or picks one of four points it cannot tell apart whose stresses differ by two thirds.

The library, page 3 of 4 — where weld-group sits