Experimental - theoretical study of axially compressed cold formed steel profiles

Abstract

Analysis of axially compressed steel members made of cold formed profiles presented in this paper was conducted through both experimental and numerical methods. Numerical analysis was conducted by means of "PAK" finite element software designed for nonlinear static and dynamic analysis of structures. Results of numerical analysis included ultimate bearing capacity with corresponding middle section force-deflection graphs and buckling curves. Extensive experimental investigation were also concentrated on determination of bearing capacity and buckling curves. Experiments were conducted on five series with six specimens each for slenderness values of 50, 70, 90, 110 and 120. Compressed simply supported members were analyzed on Amsler Spherical pin support with unique electronical equipment and software. Besides determination of forcedeflection curves, strains were measured in 18 or 12 cross sections along the height of the members. Analysis included comparisons with results obtained by different authors in this field recently published in international journals. Special attention was dedicated to experiments conducted on high strength and stainless steel members.Analiza rezultati numericke simulacije su granicna sila, odgovarajuca pomeranja-ugibi stapa sredine uzorka i krive izvijanja stapova. Sprovedena su i obimna eksperimentalna ispitivanja nosivosti stapova pri izvijanju. Eksperimentalna ispitivanja nosivosti obuhvatila su pet serija od sest uzoraka sa vrednostima vitkosti 50, 70, 90, 110 i 120. Pritisnuti prosti stapovi analizirane su kroz Amsler testove u kojima su korisceni sferni oslonci. Koriscena je nova elektronska oprema i originalni softveri. Pored merenja nosivosti i deformacija belezeni su i rezultati istezanja u 18 do 20 tacaka duz poprecnog preseka. Analizirani su i rezultati najnovija istrazivanja razlicitih autora iz ove oblasti za visokovredne i nerdjajuce celike i izvrsena su poredjenja.