Research Of Active Vibration Control Of He Bridge

The development of national economy has brought drastic competition of the communication and transportation business. Air transportation and waterway carrier put forward strong challenge to land transportation, and the bridge plays an important role in the land transportation.New development of designing technique and material performance makes building softer bridge structure possible, but the structure is easy to destroy by action of load, especially moving load. The deformation and vibration caused by heavily loaded car of high speed influences the security and use of the bridge greatly. Vibration control that uses controlling facilities is an effective method of suppressing the bridge response, and it is very important to improve the security and use of the bridge structure.Passive vibration control does not need external energy, whose device structure is simple, and easy to realize, but difficult to meet high demand to vibration environment, products and structure vibration control. Active control technique has been used more and more widely in engineering because of its many advantages such as good effect, strong adaptability, high precision and so on.In this paper, we introduced briefly the principles and development of various kinds of vibration theories and explained the core of active control — design method of control law. Using open ring control method, the active moment control to moving load may reduce the moving response and remove the resonance of the bridge. Because a large amount of application of bridge structure on expressway, it is necessary to consider the car-bridge action synthetically. By forming an integrated large system including the car and bridge structure system and considering the interaction of the wheel/bridge as the "link" between these systems, the study focuses on the car — bridge coupling dynamics. Based on the summary and digestion of the predecessor's research experiences, applying optimal control method and using symmetrical moment, we analyzed the coupling dynamic of the car and the bridge, which may reduce the response of the bridge effectively when vehicle undergoes. What's more, using edited computer program based on symbolic method, we can get the value of Riccati equation (which is the key to solving the optimal control law). Matrix operations programmed as respective modules, other relevant work of application program can be simplified, and Riccati equation can be referred in other fields.When the vibration of the bridge is controlled, the vibration of the vehicle can be controlled accordingly, which can not only reduce the damage to the car but also improve the security and comfortableness of the car.