Active Control For The Longitudinal Seismic Response Of Tianxingzhou Bridge

As widespread flexible construction of long-span bridges and extensive application of efficient construction materials, the issue of bridge structure vibration has become increasingly prominent. The vibration issues, especially the longitudinal vibration, are not only related to the safe operation of bridge but also related to a successful rescue work after disaster. Structural vibration control, as a kind of active strategy, withstanding the external power input with the teamwork of the control system and the structure, can effectively reduce the structural dynamic response.The study on the way of active control can promote the development of the active control theory and improve the engineering earthquake-resistance technique,which has important theoretical meanings and utilities.Taking Tianxingzhou Bridge as the project background, the analysis to the control the longitudinal seismic response of the main deck is done.and also the time-delay issue in the semi-active control system is discussed,which followed by the polynomial interpolating compensation algorithm. Through the results of the bridge vibration control when the bridge is exerted by a seismic shock,this the active control method is verified to be effective in the longitudinal vibration control of the cable-stayed bridge. In this paper:(1) Dynamic characterisc analysis of Tianxingzhou Bridge. The paper systematically introduces the process of building the Ansys model of Tianxingzhou Bridge.Ten modes are selelcted,so is the ansys mass.(2) Time-delay compensation of the active control system.Time-delay and its compensation are important issues in optimal design of semi-active structural control system. In this paper,the reasons for the time-delay and its influence on the control system are analyzed.Polynomial interpolating compensation algorithm for the time-delay of the active structural control system is proposed, which is proved to be valid through a frame structure numerical example.(3) Computation for the longitudinal seismic response control of Tianxingzhou Bridge.In a vibration control system, control strategy determines the control effect. The optimal control of structure under external loads is calculated in the LQR algorithm, and then combined with the forward states of the actuator; we predict the next force the of the actuator in the polynomial interpolating compensation algorithm so as to compensate the influence the time delay brings.Numerical analysis shows that the scheme of using the active control for the longitudinal seismic vibration control of Tianxingzhou Bridge is feasible.