| With the continuous rise of high-rise buildings,the development of elevators in the direction of high-speed and ultra-high speed has become a general trend.High-speed elevators will have more severe vibration problems due to faster operation speeds,which will seriously affect the operation safety of elevators and passengers'ride comfort.Therefore,exploring the mechanism of vibration response of high-speed elevators has certain theoretical guiding significance for design,manufacture and installation.In the high-speed state,the vibrations of the car,the guide shoe and the guide rail are mutually restrained and constitute a car-guide shoe-guiderail coupling system.As the random parameters and random excitations brought by high-speed elevators,such as manufacturing errors and installation errors,become increasingly prominent,the traditional deterministic structural dynamic analysis methods can no longer meet the analysis requirements.In addition,high-speed elevators are mostly used in high-rise and super high-rise buildings.Super high-rise buildings are a typical wind-sensitive structure.The wind-induced vibration effect inevitably brings about the vibration response of the guide rails fixed to it.Therefore,considering the influence of wind induced vibration response of super high-rise buildings,the requirements for the theoretical modeling of high-speed elevators are put forward.On the other hand,the guide rail and the guide roller are the main components of the guide system.The non-smooth interface contact constitutive relationship of the wheel and rail directly affects the dynamic response of the high-speed elevator.Therefore,detailed analysis of the impact of random factors and wind-induced vibration of super-tall buildings on the vibration response of the high-speed elevator coupled system is carried out,and the contact mechanism of the wheel-rail interface is studied to establish a more practical analysis method,which has a bearing on the improvement of high-speed elevator ride comfort.Positive significance.The main research contents and results are as follows:?1?According to the Bernoulli-Euler theory,the differential equations of the forced vibration of the guideway are established,and the vibration equations of the roller and the car are respectively established using the D'Alembert's principle,and finally the guide rail is established through the relationship between the force and the relative displacement between them.Guide shoe-car coupling system vibration model.The mode-superposition method is used to solve the mathematical model of the partial differential coupling system.Based on the analysis of the relationship between the length of the guide rail,the unit length of the guide rail and the bending rigidity of the guide rail,the structural parameters of the guide rail are obtained and the dynamic characteristics of the guide rail are obtained.The law of influence.The calculation results show that the flexural rigidity of the guide rail mainly influences the vibration deflection of the guide rail.The unit length of the guide rail mainly affects the flutter of the guide rail.The length of the guide rail has significant influence on the vibration deflection and vibration of the guide rail.?2?In view of the randomness of the structural parameters of the guide rails that are objectively present in the manufacturing and installation process of high-speed elevators,based on the coupled rail-shoe-seat-car dynamics model,the stochastic perturbation theory and discrete numerical solution are used.Methods Randomized parameter sensitivity and standard deviation analysis were performed.The results of the example show that the vibration acceleration response of the guide rail is the most sensitive to the length parameter of the guide rail,and the vibration displacement response of the guide rail is the least sensitive to the elastic modulus of the guide rail.?3?The increasing number of elevators with large payloads and high speeds and the increase in elevator speed and load capacity have made the wheel-rail interaction and wear more and more serious.Based on the rail-shoe-shoe coupled vibration model,using the model equivalent method,the wheel-rail parameters are introduced into the coupled vibration model and the numerical values are discretized.The step-by-step integration method under discrete variables is used to explore The influence of the wheel-rail parameters on the horizontal vibration of a high-speed elevator car.The results of calculation examples show that in order to obtain satisfactory dynamic comfort of the elevator,the unevenness of the roller surface should be controlled in the order of1×10-5 m;the vibration of the car due to the excessive roundness of the roller should be prevented;Loosening of the brackets should avoid the momentary exacerbation of the car vibration caused by loosening of several consecutive rail brackets at the same time.?4?Based on the dynamic model of the guide rail-guide shoe-car coupling,the theory of wind-induced vibration of super high-rise buildings in building structural engineering was introduced,and the vibration model of high-speed elevator coupled system with wind load impact was established and further developed.The influence of wind pressure and building height on the vibration of a high-speed elevator coupled system was studied.?5?With the help of the 120m elevator test tower of Shandong Fuji Elevator Co.,Ltd.,a horizontal vibration test platform for the high speed elevator coupling system is built with the help of the project.According to the simulation calculation of the coupled system model built by the company FJK-X-8000 7m/s high speed elevator,the horizontal vibration acceleration response curve is obtained.Then,on the horizontal vibration test platform,the DT-4A elevator accelerometer is used to carry out the horizontal acceleration test of the FJK-X-8000 high speed elevator,and the simulation calculation is carried out through the analysis and simulation.Results and typical data characteristics of real ladder test data verify the correctness of the coupling system model,wheel rail interface contact mechanism and algorithm. |
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