| With development of real estate industry, more and more tower cranes are used in the construction of building. Tower crane structure vibration and payload swing produced by the vibration is a problem that we cannot to be ignored.The article mainly through two kinds of modeling method to establish the dynamics model of tower crane, one is based on the theory of beam dynamics modeling of tower crane, the second is established based on finite element mechanics equation and the dynamic response analysis of tower crane. To eliminate or suppress after payload swing interact with structural vibration caused by the coupling vibration to lay a theoretical basis. This paper studies the main work is as follows:(1)The tower crane jib is simplified as a cantilever beam, the hoisting by wire rope connected to the moving trolley, that establishes the relationship between the beam, the trolley and the payload. Firstly, the dynamic vibration differential equation is established. Secondly, system dynamics models of the trolley the payload are established. Finally, the vibration equation about the girder, trolley, and payload is established. By analyzing the vibration equation, modes interact each other by mobile payload, and mobile payload transfers energy between the modes of the beam.(2)_Based on the idea of finite element, the Lagrange equation is set with Rayleigh dissipative function of a tower crane. Based on the assumption about small pendulum angle and a rigid structure, the coupling vibration equation is simplified, and the load swing natural frequency is simulated. Based on spherical pendulum and plane pendulum of the payload, the dynamic equations with tower crane structure vibration and payload swing are set by applying a small load.(3)_By using ANSYS software to model tower crane, the vibration natural frequency of tower crane structure is got, and the top five order natural vibration modes of the tower crane are simulated, and the harmonic response of tower crane is analysed. |
PDF Full Text Request