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Analysis of trusses2D

Method of joints

Use joints, sections, geometric rules, rank checks, and moving-load envelopes for determinate trusses.

Open the complete lesson
Interactive engineering simulation

Method-of-Joints Truss Solver

Select a joint, inspect its free-body diagram, and verify the two scalar equilibrium equations.

Rigid-body statics
explore task
Choose a joint with no more than two unknown member forces. Predict tension or compression before revealing values.
AB: 66.7 C kNAB 66.7 CBC: 66.7 T kNBC 66.7 TCD: 66.7 T kNCD 66.7 TDE: 66.7 C kNDE 66.7 CAC: 53.3 T kNAC 53.3 TCE: 53.3 T kNCE 53.3 TBD: 106.7 C kNBD 106.7 CSelect joint AASelect joint BBSelect joint CC80 kNSelect joint DDSelect joint EEA-Ry: 40.0 kNE-R: 40.0 kN
Joint load
80 kN
kN
10–180

Drag for exploration or enter an exact value. Press Enter to apply; Escape restores the current value.

Truss height
3.00 m
m
1.50–6.00

Drag for exploration or enter an exact value. Press Enter to apply; Escape restores the current value.

Joint A residual: 0.00e+0 kN. First incident result: AB = 66.7 C kN.
Max joint residual
1.42e-14
Assumption
Pinned, axial-only
Diagrams are schematic equilibrium models. Member lines do not show elastic deformation, buckling, connection flexibility, or second-order effects.
Model scope and verification

Use the displayed units and idealizations, then verify the governing balance or compatibility equation before interpreting the result.

Related simulations

Method of sectionsZero-force membersStability and determinacyBridge moving load