Mehmed Čaušević

Nonlinear seismic analysis of steel frame with semi-rigid joints

U radu je prikazana nelinearna seizmicka analiza celicnog okvira bez dijagonala, pri cemu je uzeto u obzir stvarno ponasanje realnih djelomicno krutih prikljucaka na nacin da je za odabrani prikljucak prethodno provedena numericka simulacija. Rezultat toga je dijagram odnosa momenta savijanja i rotacije prikljucka, koji je aproksimiran kao trilinearan, i ukljucen u seizmicku analizu primjenom nelinearne staticke metode N2. Određeni su apsolutni i relativni pomaci okvira te izvrsena usporedba dobivenih rezultata s rezultatima za celicni okvir s apsolutno krutim prikljuccima.

ČELIČNI PLOŠNI ELEMENTI OPTEREĆENI U SVOJOJ RAVNINI: FAKTORI IZBOČIVANJA

The aim of this paper is to present the way how the values of buckling factor are derived, which are provided as a ready-made numerical values in the existing literature on steel structures and European standards for steel structures. In this paper the stability of steel plate elements loaded in their plane is presented in the way how this problem is solved in mechanics. The general theory of stability of plates is given and the equation of buckling of plate elements is derived. The elastic critical buckling stress for plate cr  is explained as well as the plate buckling factor  k for arbitrary boundary conditions, arbitrary distribution of external loading on the plate and arbitrary relationship between length and width of the plate. In addition the values of buckling factor for various boundary conditions and arbitrary relationship between length and width of the plate are presented using the diagrams in the literature. Finally, an example of a plate element calculated analytically and computed using specialized software package EBPlate [11], which is based on the European standard EN 1993-1-5 [3], is presented.