Buckling of a movable constrained laminated beam with variable-length in hygrothermal environment

Abstract

The buckling response of a variable-length laminated beam constrained by a pair of symmetrical walls in hygrothermal environment is studied in the paper. The constrained wall is rigid but supported by springs that move upwards as a whole after being subjected to a force. The nonlinearly constrained buckling governing equation of the variable-length laminated beam in hygrothermal environment is established based on the principle of minimum potential energy and the Lagrange multiplier method. The buckling responses of the variable-length laminated beam are derived based on the elliptic integral method. Extensive numerical calculations are performed to illustrate the effects of different constraint clearances, spring stiffness, geometry, temperature, humidity, and composite fiber ply angle on the critical buckling load, buckling response, and buckling path.