Truss Diagonal Member Force
Truss Diagonal Member Force
Truss diagonals resolve the panel shear into axial force; resolving vertically at a joint gives the member force directly.
For a diagonal at angle θ, F = P/(2·sin θ). where P is the applied load shared and θ the diagonal’s angle to the horizontal.
Inputs
P := 60 kN=60000 N
theta := 0.7854=0.79
Resolve the load into the inclined member.
F := P/(2·sin(theta))=42426.33 N
Results
Steeper diagonals carry less force but need more of them. The sign (tension or compression) follows from the truss geometry and load direction.
Assumptions & limitations
- Pin-jointed, statically determinate truss.
- Loads at joints only.
- Members carry axial force only.