Stiffness Analysis And Optimization Research On The Guide Frame Structure Of Lifting Work Platform

The demand,span and load of the lifting platform are increasing with the development of the construction industry.As the supporting and bearing structure of working platform,the guide frame structure reaches up to hundreds of meters.The strength,stiffness and stability of the guideframestructure is the key to elevating work platform design analysis.In view of the research on the structure of the guide frame of the lifting platform at home and abroad,the research on stiffness is less than that of stability.This thesis focuses on the stiffness analysis of the guide frame structure of the lifting platform,which not only has far-reaching theoretical significance,but also has great practical value for engineering.Firstly,based on the standard of' lifting platform,four different working conditions were selected to analyze the load under different working conditions.The finite element model of the large span lifting platform,the guide frame structure,the chassis structure,and the operating platform were established,and the statics analysis of the whole structure,the guide frame structure,the chassis structure,and the operating platform werecarried out.The whole structure,the guide frame structure,the chassis structure,and the operating platformstress and deformation cloud chart were obtained.The frame structure was determined as the most dangerous structure,andthe ability of stiffness was the key factor affecting the performance of the machine.Secondly,the simplified model of the chassis structure and the wall frame structure were established,and a basis was provided for rigid frame structure.The influence of the parameters on the rod parts and the arrangement mode on the static stiffness of the guide frame were analyzed.The basis for optimizing the structure of the guide frame was provided.Thirdly,the stiffness analysis of the structure of the guide frame was analyzed,and the natural frequencyas a measure of the dynamic stiffness of the guide frame was determined.The second degree of freedom dynamics model of the guide frame structure was established by the centralized quality method.Modal analysis of guide frame structure was carried out,and the accuracy of the model was verified by the method of theoretical calculation.Harmonic response analysis of guide frame structure was carried out to find out the natural frequency range of resonances,which can provide the basis for the optimization of the guide frame structure of the lifting platform.Finally,based on the analysis of static stiffness and dynamic stiffness,a variety of parameter combination schemes were given by changing the chord member and the web memberof the guide frame of the section size and thickness,the spacing and the constraints of wall frame structure.The optimization study of the optimized scheme parameters was carried out.The stability of the guide frame was verified after the optimized size,and the optimal design scheme was obtained.Using the theory of material mechanics,steel structure,structure dynamics and finite element method,the static stiffness of the guide frame was analyzed.The method of the rigid definition of the guide frame was obtained.Based on the influence of the cross-section size of the guide frame on the static stiffness of the guide frame,the parameter optimization of each section size of the guide frame was carried out.The cross-section ability of the guide frame can be fully developed,which can provide some guidance for the design and development of similar products.