This diploma thesis deals with resistance of plate girders subjected to stresses due to bending according to four proposed methods. Two of them are introduced in SIST EN 1993-1-5 standard. These are reduced stress method and effective width method. The other two proposed methods are effective width method derivates. The first part of thessis introduces rules for determinig bending resistance in respect of plate buckling due to direct stresses.\ud
In the second part of the thesis the comparison between elastic critical plate-like buckling stresses calculated according to simplifyed analytical methods from SIST EN 1993-1-5 and elastic critical plate-like buckling stresses calculated with EBPlate software.\ud
The final two parts of this diploma thesis contain comparison of sugessted methods at the level of different geometric parameters and comparison of sugessted methods with results of numerical simulations. Calculations were made with software developed with Matlab. Calculated and analyzed were more than 5000 cases of different plate girders. Parameters that we varied are: location of stiffener, web slenderness, ratio between width and height of web, stiffenes of the stiffener, ratio between section area of web and section area of flange, ratio between section area of compression and tension flange, number of stiffeners. Numerical simulations were made with Abaqus software
