Strength of steel I-girders subjected to eccentric patch loading

• A mechanical model for the ultimate strength of I-girders subjected to eccentric patch loading is presented.
• The methodology is based on the plastic collapse mechanism.
• The model accounts for the influence of the eccentricity and the flange-to-web thickness ratio on the strength.
• Predicted strengths are in good agreement with experimental results.

This paper presents a methodology to determine the ultimate strength of I-girders subjected to eccentric patch loading. The methodology is based on the plastic collapse mechanism observed experimentally, in which yield lines are formed in both the flange and the web under the action of the applied load. A mechanical model is developed accounting for the influence of the eccentricity and the flange-to-web thickness ratio on the load carrying capacity of the girder. Ultimate strengths are calculated according to the proposed methodology and the theoretical predictions are compared with available test results, showing that the predicted ultimate loads are in good agreement with experimental results.