State Space Control Algorithm Of Architectural Structure Under3D Seismic Excitations

Structural vibration control is an effective measure for reducing the structuralresponse under the external excitation. The excitation which the civil engineeringstructures are faced with is usually random load, such as strong wind, sea wave,stream and earthquake. But the existed earthquake records are often used in previouscontrol analysis. The shortage is that the ground motions of the structure can’t bereflected preferably, and then the controlled effect is affected. Based on equivalentexcitation method, the equivalent excitation load is constructed according to the sitecondition and frequency spectrum values, and mature control algorithm is adopted toimplement the random vibration analysis.In addition, aim at the structural vibration control problem undermulti-dimensional seismic excitations, state space control algorithm is implementedin the paper to solve it. The significance of this research is that the real earthquakemotion usually contains multi-dimensional excitations. So in order to simulate thereal seismic emotion of the structure, the rotational component and the proper Cariolisaccelerations must be considered in the seismic excitations. Based on themulti-dimensional vibration control model of structure established by Prof. Sun zuoyu,in the paper, the symplectic conservative perturbation to present the algorithm is citedto solve the multi-dimensional vibration control problem. Therefore, the algorithm isput into practice, and preliminary exploration for theory analysis and numericalsimulation of the structural vibration control is given.Based on the analysis above-mentioned, the main research contents are asfollows:1. Based on the equivalent excitation method, the equivalent excitation load ofthe controlled system is constructed under random excitations, and then the statespace control theory is adopted, the responses of the controlled system are calculated.According to the equivalent excitation method, the statistical characteristics of theresponses are determined to fulfill the random vibration analysis of the controlledsystem. The simulation analysis of a real building shows that the LQG controlledstructural has remarkable control effect. And that prove the feasibility andeffectiveness of the random vibration analysis for the controlled system.2. The research of structural dynamic analysis under multi-dimensional excitations. Based on state space control theory, it is discussed that the numericalanalysis method of solving the dynamic equation of the structure. The seismicexcitations considered the rotational component and the proper Coriolis accelerations.Since the new presented equations is remarkable nonlinear, this paper cites thesymplectic conservative perturbation to present the algorithm to solvemulti-dimensional vibration control, and put the algorithm into practice by usingMATLAB programs.3. Numerical simulate analysis. Taking the real structure for example, theinfluence effect of the multi-dimensional vibration control mode in differentconditions is analysed in the paper.