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Frames and machines2D

Compound frame

Disassemble connected rigid members, preserve action-reaction pairs, and calculate force transformation through mechanisms.

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Interactive engineering simulation

Compound Structural Frame

Analyze a loaded member restrained by a two-force link and a pin support.

Rigid-body statics
explore task
Identify the two-force link before writing the three equilibrium equations for the loaded member.
Member AB FBDA reactionB: (-10.0, 12.0) kNLink BC FBDB: opposite pairAxial force 15.6 kN
Supported load
24 kN
kN
5–80

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

Link horizontal run
2.50 m
m
0.50–5.00

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

Link vertical drop
3.00 m
m
0.50–5.00

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

Two-force link
15.62 kN compression
Pin-pair check
0.00000 kN
Equilibrium residual
0.000000
FB,1=−FB,2\mathbf{F}_{B,1}=-\mathbf{F}_{B,2}

A member pinned at only two ends with no intermediate load is treated as a two-force member. Otherwise, retain all pin components and moments required by equilibrium.

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

Frame disassemblyPulley-supporting frameLever or bolt cutterExcavator or crane linkage