Random Earthquake Response Analysis Of Gantry Crane

China is an earthquake prone country,which have been stricken many times by earthquakes up to magnitude 7 in recent ten years,These natural disasters greatly endanger the social and economic development,as long as people’s lives.Gantry crane is a common material handling equipment,which has been widely used in wharf,construction site and shipyard and so on.As the structure of crane becomes more and more big and complex,the influence of the dynamic characteristics on the structure gets more and more obvious in seismic analysis.However,only static analysis is required in gantry crane seismic analysis,which cannot be consistent with the actual result.In order to avoid related accidents,detailed seismic analysis is very important in practice.In this paper,the dynamic seismic characteristics of gantry crane is numerically studied with ANSYS,detailed contents are given as follows:1.Finite element model establishment and static analysis.The gantry crane finite element mode was built in ANSYS based on the simplify of gantry crane structure.The corresponding static analysis of gantry crane under the condition of rigidity,strength and earthquake was then made with the model based on the requirements of the current specifications.2.Introduction of the response spectrum theory and the theory of random vibration analysis.Based on the theory of response spectrum,the seismic response spectrum curve was obtained.Farther derivation of the mathematical description of the structural seismic analysis and the dynamic response equation of the structure under random seismic excitation was made based on the theory of random vibration.3.Modal analysis.Modal analysis of the gantry crane was applied with the APDL command flow.The gantry crane’s first 10 order vibration frequencies,vibration mode and modal participation coefficients in each direction are discussed based on the analysis.4.Random seismic response and spectrum analysis.With the response spectrum curve and the theory of random vibration analysis,the response spectrum and random seismic of the gantry crane was analyzed under uniform excitation,and spatial effect model and related parameters was selected in the present work,Traveling wave effect,coherent effect and site effect on the crane structure were considered respectively,and comparison was made between the results of uniform excitation and these cases.5.Analysis of factor influence.The research on the influence factors of the gantry crane in the earthquake are made under different site types,input angles and different conditions,and the corresponding influencing rule were discussed by analyzing the simulation results of the structural stress.