Technical Lateral Buckling, Stress and Strain Analysis of Semi-slender Thin-walled Cylindrical Pinned Column made of Steel St35 Simplified with Aall, Jzall, E= Ec , Epl= Esc

The paper continues and discusses the next case of the simplified method of the Technical Stability Theory (TSTh) of loss of stability of lateral buckling in elastic-plastic states of semi-slender columns axially compressed by a force. It is again assumed that in the critical elastic-plastic transverse cross-section there are the elastic and plastic parts of the area, keeping strength. Here it is assumed that in the elastic-plastic transverse cross-section, the entire transverse cross-section of the column keeps the resistance, i.e. the transverse cross-section area A= Aall, the moment of inertia of a cross-section area Jz= Jzall as well as is assumed that the elastic Young’s modulus E= Ec features the elastic static moment Szel, and the plastic modulus Epl features the plastic static moment Szpl. The next assumptions are that the elastic Young’s modulus E is varying with the slenderness ratio  and equals the compress modulus, i.e. E= Ec(Lambda) taken from the experimental research, and also is varying with the transverse cross-section area A, i.e. E= Ec(Lambda, A). The graphs of the functions of the curved axes, their slopes, deflections, stresses and strains of the thin-walled cylindrical column D45x1x545 mm with slenderness ratio Lambda= 35 as well as the critical compressive stresses depending on the cross-section areas A and slenderness ratios Lambda are presented as the theoretical examples with the new assumptions and compared to results obtained from experiments with thin-walled cylindrical columns made of steel St35.