Design And Optimization Of Double-beam Bridge Erecting Machine For Multiple Working Conditions

With the rapid development of technology and economy,bridge erector equipment is used in the construction of infrastructure,which plays a vital role in improving traffic convenience and promoting the development of urbanization.Restricted by the construction terrain and environmental conditions,special bridge types such as large longitudinal slope bridges,large transverse slope bridges,oblique bridges,and small curvature arc bridges have emerged,which pose new challenges to the performance of bridge erection equipment.Therefore,it is of great significance to develop a new type of bridge erecting machine to meet the needs of erecting these special bridges.By analyzing the structural characteristics of bridge erecting machines at home and abroad,as well as the design method of bridge erecting machine structure,a double-beam bridge erecting machine suitable for multiple working conditions is designed.The structure composition,main performance parameters of the double-beam bridge erecting machine and the operating procedures for erecting straight bridges,gradient bridges,and inclined bridges are described in detail.The allowable stress method is used to design and calculate the main structure of the double-beam bridge erecting machine,and the cantilever working condition,the first working condition of the span,the middle-span working condition,the end working condition and the side of the bridge when the bridge erecting machine passes through the hole and the beam are selected.Perform theoretical calculations on beam conditions to determine that the rigidity,strength and stability of the main beam structure meet the allowable requirements.Use ANSYS Workbench to analyze the statics,modal and harmonic response of the main girder structure under the via hole and girder erection operation,and compare the simulation results with theoretical values to verify the rational design of the main girder structure.Comprehensive analysis of statics and dynamic simulation results shows that the main girder structure is reasonable in design and has sufficient safety margin.on this basis,based on the response surface model and the combination of MOGA and Screening algorithm,the multi-objective optimization design of the main beam is done.The section dimension of the primary beam is selected as a design variable,and the mass of the main girder is decreased under the premise of meeting the requirements of intensity,rigidity and dynamic performance.Analyze and compare the optimization results of the two algorithms,obtain the optimal design plan,and perform simulation verification on the optimized main girder.The results show that the optimized main beam structure is reduced by 9.8%,and the static and dynamic properties meet the allowable requirements.This optimization method saves material consumption and manufacturing costs,and provides theoretical guidance for the optimization of related bridge erecting machine structures.