We analyze the collective buckling of a row of rigid beams with their lower ends built
into an elastic substrate. The beams interact among themselves through the
deformation of the substrate. The present analysis is more sophisticated
than previous ones in that the lower ends of the beams are allowed to move
vertically and horizontally, in addition to rotation. From the linear theory of
elasticity and rigid body statics, an eigenvalue problem is formulated and
solved. Calculations showed that periodic deformations resulted atop the
compliant substrate after restrictions on the beam base displacements were
released. Consequently, the refined model found good match with the height
measurements from Atomic Force Microscope (AFM). Our work suggests
that both the compliant substrate and the interaction of neighboring beams
through the deformation of the substrate dominate the collective buckling.
Furthermore, these results contribute toward the understanding, design and
application of soft nanostructures produced by soft lithography in a variety of
fields.