By l?. Rein itzhuher

When thin-walled columns formed from flanged sheet, such ‘“ as used in airplane construction, are subjected to axial load, their behavior at failure varies according to the slenderness ratio. On long columns the axis deflects laterally while the cross section form is maintained; buckling results, The re-spective breaking load in the elastic range is computed by E~le~:s formula and for the plastic range by the Wngesser-Karman formula. Its magnitude is essentially dependent upon the length. On intermediate length columns, especially where open sections are concerned, the cross seotion is distorted whi~e the cross section form is preserved; twisting failure results. The buckling ” load in twisting is calculated accord-ing to Wagner and Kappus (reference 1). On short columns the straight walls of low-bending resistance that form the column are deflected at the same time that the cross section form changes- buckling occurs without immediate failure. Then the buckling load of the total section computable from the buckling loads of the section walls is not the ultimate load; quite often, especially on thin-walled sections, it lies considerably higher and Is secured by tests. Both loads, the buckling and the ultimate load are only in a small measure dependent upon length. The present report is an attempt to theoretically inves-tigate the behavior of such short, thin-walled columns above,. the.,b,uckli,ng,load with the conventional calculating methods. *fiBeitrag zur Berechnung gedriickter, diinnwandiger Profile oberhalb der Beulgrenze, ~ Luftfahrtforschung, vol. 19, no. 7