Analysis of locally loaded steel plate girders: Model for patch load resistance

• An exp. research of steel plate girders subjected to patch loading is presented.
• Ultimate load is reached due to buckling of the isolated web plate under the load.
• The mathematical model for calculating ultimate load capacity is proposed.
• The proposed model is stable and it provides a realistic prediction of ultimate load.
• The EN1993-1-5 model shows signs of instability and underestimates ultimate load.

The paper deals with the problem of ultimate load capacity of thin-walled steel I-girders under the patch load which acts in the web plane of the girder. It considers the patch load type “a” according to EN1993-1-5. The analysed problem is very complex with the girder carrying capacity loss due to buckling of the web under the loaded flange. An experimental research of twelve plate steel girders subjected to patch loading is presented. The mathematical model for calculating ultimate load capacity of thin-walled steel I-girder under the patch load is proposed. Experimentally obtained ultimate loads and ultimate loads calculated by EN1993-1-5 are compared with those calculated by the proposed model. Experimental database consists of 52 tests from the experimental researches which were done at the Civil Engineering Faculty, University of Montenegro.