Truss Bridge Failure Lab

Member buckling, overload and modular bridge loads: a 2-D pin-jointed truss solved by the direct stiffness method, with Euler/Johnson capacity checks and a progressive-failure cascade.

Scenarios

Structure

Truss type

Stacked panels

Span

Depth

Panels

Material

Right support

Counter-diagonals (adds redundancy)

Members

Chord tube ⌀

Web tube ⌀

Eff. length K

Buckled members keep 30% of P_cr (ductile)

Wall = D/16 (steel), D/12 (aluminium), solid for timber. K = 1 for pinned ends.

Loads

Vehicle symbol

Position

Overload factor

Temperature ΔT

Deck dead load

A generic 3-axle load symbol (20/40/40 % axle split). One of the two trusses carries half the weight.

Display

Deflection scale

Quality

Display scale is auto-limited so the bridge stays readable. Tube thickness is exaggerated about 2x.

Readouts

Selected member

Click a member in the 3D view or the chart.

Checks against theory

The science