| Structure dynamic analysis generally includes numerical calculation method and physical experiment method. The numerical computation method has become a commonly used method in the engineering sector, and especially it is already mature in solving the problem of flexibility. During the nonlinear analysis of structures under external bads, there are still shortages of poor convergence, time-consuming, etc. For physical experiment method is concerned, because the building structures in the civil engineering are usually bulky, large-scale, etc., the model experiment is generally used in the experimental method, it can intuitively reflect the response characteristics and failure modes of structure under the external load, but the model experiment is often expensive and time-consuming.It is pointed out that the structural dynamics equation and RLC circuit equation have the same form of mathematical expressions. The consistency of this mathematical form to a certain extent reflects that both have some common laws in the physical nature. This paper take circuit theory used in structure dynamic analysis basing on mechanical and electrical analogy method and carry out the structural dynamics analysis method in-depth based on the electrical circuit analogy. Le., electrical circuit analogy method.The research work done in this paper can be summarized into several aspects listed as follows:(1) The establishment of the equivalent analog circuit. Because the structural dynamic equation and RLC electrical circuit equation have the same form of differential equations mathematically, by means of the electrical circuit analogy method, the analogy between the mechanical quantity in the structural dynamic system and the electrical quantity in the electrical circuit system is carried out, and the electrical circuit equation is obtained. Based on the circuit design principle, the equivalent analog circuit of structural dynamic system is obtained.(2) The comparative study of structure dynamic analysis method and electrical circuit analogy method. The mechanical model of single-degree-of-freedom structural dynamic system and multiple-degree-of-freedom structural dynamic system are established. Using the numerical analysis method (Wilson-0), the procedures to solve the structural dynamic equation are presented. And the structure dynamic response is obtained. Through the electrical circuit analogy method, designing the structural dynamic system into the equivalent analog circuit and using the software MULTISIM to circuit simulation analysis, the circuit reaction information is obtained. Using the equivalent circuit design method, the circuit reaction can be restored to the structural dynamic response. And the results are compared with the results of the structure dynamic system. The results show that the circuit designed by the method of equivalent circuit design can obtain the consistent results of the structure dynamic system.(3) Experimental study. On the basis of the equivalent circuit diagram, the circuit is connected by electrical component. The voltage of the capacitor is measured by oscilloscope. The experimental results and the numerical simulation results of MULTISIM are compared. And experimental error is analyzed. The results show that circuit experiment can get the consistent results of the numerical simulation results. So using the electrical circuit analogy method, the problems of the structure dynamic system will be solved.Research results shows that the electrical circuit analogy method is an effective and practical method on solving structural dynamic problems. The experiment results agree well with the numerical simulation results. But in the problems of multiple-degree-of-freedom structural dynamic system and inputting an arbitrary excitation source, further studies are necessary. |
