Deformed and undeformed shapes are plotted, plus the bending moment. An equal imposed displacement load condition is applied to each case.

An equal imposed deflection is imposed at the top-left corner, stiffness has been evaluated based on the associated reaction force.

The three frame structures stiffness is reported below:

• $b/a=1/5$: $k=7.29k_\mathrm{ref}$
• $b/a=1/1$: $k=5.60k_\mathrm{ref}$
• $b/a=5/1$: $k=3.38k_\mathrm{ref}$

where $k_\mathrm{ref}$ is the stiffness of the single upright member, taken as a reference.

Beam cross section is uniform along the frame, and very slender. (MSC.Marc model)