The Vibration Control Of Bridge With Piezoelectric Intelligent Structure

The problem of the vibration of bridge under vehicles was put forward from practice. The bridge not only should bear the static, but also the effect of moving loads and the vibration inertia power of bridge and vehicles when the vehicles pass the bridge. Higher the speed of the vehicles is, more important the safety problem is. The safety of high speed vehicles and the riding comfort of passengers should be guaranteed. So it is important to study the vibration controlling technology of bridge.Rencently, the piezoelectric materials have been widely used in the field of structural vibration control as a new type of smart materials because of their excellent materials characteristics. Much research work on active vibration control has been performed. The research work of this thesis consists of six chapters:In chapter one, the mechanical and electrical characteristics of piezoelectric materials and their civil engineering applications are described. and introducing the main research work of the paper.In chapter two, the direct and inverse piezoelectric effect of piezoelectric materials are studied. The actuating and sensing abilities for the embedded piezoceramics are discussed in details. Consequently, the actuating equations,when piezoceramics work as actuators, and sensing equations, when piezoceramics work as sensors, are derived.In chapter three, After analyzing the piezo actuating moment equations, the optimal deepness and optimal thickness for the embedded piezoceramics in bridge and T bridge are given with explicit expressions. The conditions, by which the optimal values can be got, are also derived using inequalities.In chapter four, Bridge vibration system Modeling. The paper Systematic introduces the evolution of the vehicle-bridge dynamic system modeling. From simple system to complex system, a series dynamic equation are set up such as the equation of bridge exerted harmonic loading in Mobile and the equation of bridge under mobile quality on the spring.In chapter five, Numerical analysis. This paper presents a new device, which use piezoceramics smart structures to control vibration of the bridge. The optimal control of structure under external loads is calculated by the LQR algorithm,. Numerical analysis show. By analysis of the bridge vibration control effect when the bridge is exerted a moving force; this device is verified to be effective vertical vibration control of the bridge.In chapter six, summarize the research work and propose the future work...