What happens in Truss Mode?
In Truss Mode, the structure is treated as an idealized pin-jointed planar truss (kratownica płaska).
1
Frictionless Pinned Joints
Every node connection is an idealized frictionless hinge. No bending moments can be transmitted across joints.
2
Pure Axial Forces Only (N)
All elements are pure two-force members carrying only axial force N. Shear force T ≡ 0 and bending moment M ≡ 0 along all bars.
3
Color Coding & Zero-Force Members
🔵 Blue: Tension (+N) •
🔴 Red: Compression (-N) •
⚫ Grey [0]: Zero-Force Bars.
4
Static Determinacy Formula
Standard planar truss determinacy: n = (p + r) - 2k, where p = number of bars, r = support reactions, and k = number of joints.