Optimization of Welded I-Girder of the Single-Beam Bridge Cranes

This research deals with optimizing the welded I-girder of the single-beam bridge as a variant solution for this type of crane. The mass optimization is achieved by minimization of the welded I-girder cross-section area. The paper takes the following criteria as the constraint functions: strength, local stresses from the trolley wheel pressure, local buckling of the girder plates, global girder stability, deflection, relaxation time and the corresponding design-technological limitations. The hybridization of two new-generation metaheuristic algorithms, the Sine Cosine Algorithm and the Whale Optimization Algorithm, and original algorithms were used for the optimization procedures. The justification for applying these methods in solving practical engineering problems was confirmed by comparing the results with real solutions. As a result, significant material savings were achieved in this research, within the range of 39.52-51.92%. Also, comparing the results indicates the justification and advantages of the proposed hybridization procedure to the mentioned algorithms.