Postbuckling behavior of axially-compressed strips with discrete rigid constraints-a numerical study

Axially-compressed columns, or strips, with bilateral continuous rigid constraints (CRC) are known to be able to attain multiple snap-Through buckling events in their elastic postbuckling response that lead to the sudden release of strain energy from the system. This feature allows this structural prototype to be used as energy concentrators for smart applications. However, the parameters controlling the postbuckling response for such system are limited. The structural prototype discussed in this paper is that of an axially compressed strip provided with discrete rigid constraints (DRC), whereby the layout of the lateral constrains provides increased design freedom to control the strip's postbuckling features. The study is based on numerical simulations using the finite element method. Using a previously characterized CRC strip as a baseline, two DRC design groups were considered in symmetric and asymmetric layouts for a total of 15 different arrangements. Results show that DRC strips can attain elastic postbuckling responses with distinct characteristics and that the far postbuckling response can be controlled by modifying the number and the location of the constraints. Compared to CRC strips, some DRC patterns allow attaining higher mode transitions and larger kinetic energy release after the first buckling event. The ability to design for such postbuckling response features can be potentially used for energy harvesting and other sensing and actuation applications.