iris
Tension
Compression
Zero force
Nodes: 0
Beams: 0
Max force: --
Mode: Add Node

How it works

A truss is a structure made of straight members connected at joints (nodes). Each member carries only axial force — tension or compression, never bending. At equilibrium, the sum of forces at every node must be zero (ΣF = 0).

The simulator solves the system of equilibrium equations using a direct matrix method. For a statically determinate truss (m + r = 2n, where m = members, r = reactions, n = nodes), there is exactly one solution. If the truss is under-constrained, it is unstable and will fail.

  • Pin support: Prevents horizontal and vertical movement (2 reactions).
  • Roller support: Prevents vertical movement only (1 reaction).
  • Tension (+): The member is being pulled apart (blue).
  • Compression (−): The member is being pushed together (red).