Prediction of thermal postbuckling behavior of slender uniform columns on elastic foundation undergoing very large lateral deflections - a simple heuristic formulation

摘要

A simple heuristic formula to predict the thermal postbuckling behavior of slender uniform columns, subjected to uniform temperature rise from its stress free condition, undergoing very large lateral deflections, when the two ends of the column are restrained to move axially, is presented in this paper. The use of the von - Karman nonlinear strain - displacement relation, which contain the nonlinear term in the lateral deflection, suffices when the deflections are moderately large, i.e. of the order of the characteristic length of the column (radius of gyration r). While dealing with the very large lateral deflections, it is necessary to consider the nonlinearity due to the axial displacement also. An attempt is made in this paper, to obtain an analytical formula to predict the thermal postbuckling behavior of slender uniform columns undergoing very large deflections, by using the tensile load terms arising from the nonlinear terms corresponding to the lateral deflection and the axial displacement. The numerical results obtained from the heuristic formula, when the foundation parameter is zero;;match very well with those available in the literature, which validates the proposed heuristic formulation.