Geometric and Material Nonlinear Analysis of Structures Comprising Rectangular Hollow Sections

摘要

A nonlinear finite element analysis is presented of structures comprising thin walled rectangular hollow sections. Nonlinearities due to both the change of geometry and material yielding are included, incorporating also the effects of strain unloading. The geometry and the stiffness of the elements are modified and used to update the structure tangent stiffness matrix. An iterative procedure combining the arc length and the work methods is employed for the solution of the incremental equation of equilibrium. The method was applied successfully to predict the nonlinear load deflection behavior of isolated cold formed square hollow section (SHS) columns, fabricated rectangular hollow section parabolic fixed end arches, and double chord SHS trusses having different joint configurations.