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It already has some studies about identifying the buildings’ resonance periods in every kind of constructions, by using ambient vibration measuring. As for the mixed construction historic buildings, according to experiments, it discovered that there are some difference between every wall’s resonance periods, so they have to measured individually, the study’s object lies on a mixed construction historic building’s wall. Due to the historic buildings in the majority of one to two stories,they have the characteristics of lower construction ,lead to the measured signals are mixed with the environmental vibration sources, making confusions on identifying fundamental periods, which showed with multiple peaks on its ambient vibration response spectrum figure. The study will find out the liable method on identifying the mixed construction historic building walls’ resonance periods, identifying the mixed construction historic buildings’resonance periods stably,to make a authority on diagnose their structure conditions. The study make practical attestation with the walls in the Din Jin Ton(brick- and-wood mixed construction), Ban Ciao City ,uses the equipments of ambient vibration meters, to record the diachronic data of the mixed construction historic building walls and ground, and then use FAMOS(Fast Analysis& Monitoring of Signals)-the processing software of analyzing signals, to run FFT(Fast Fourier Transform),convert the time domain data into the frequency domain data, and according to the study, use the technique-frequency response function, reject the environmental vibration influence factor, and show the walls’ remarkable resonance frequency, so it is liable to identifying the resonance periods of lower mixed construction historic building walls. Finally, The study make an experiment by destroy the historic building -like wall, knowing that the destruction of walls indeed lead to the changing of resonance periods, by using the experimental attestation ,to make a authority on diagnose the structure’s destruction in the future. This thesis contains five chapters, twenty nine sections, and summed up individually as follows: The first chapter introduced the motives and the purpose of the study at the beginning, and then describes the range and the contents, and finally describes the process, the method and procedure. Expecting the readers can comprehend the framework of this thesis by reading this chapter. The second chapter-references review of the ambient vibration measuring theories and the resonance frequency functions:at first, studies the basic concept of the ambient vibration measuring and the identifying method of the resonance periods ,and then review the application conditions on the mixed construction historic buildings’ ambient vibration measuring. In the references, because the historic buildings are not rigid structures, and have confusions on identifying the walls’ resonance periods;finally, review the technique of the resonance frequency functions, by using this technique, to identifying the low-stories mixed construction historic buildings’ resonance periods. The third chapter-the principles and techniques of the ambient vibration measuring data analyses:first, studies the relation between the structure’s side strengths and the resonance periods;and then describes the way of handle and analysis data;finally introduce the measuring tools and the analyzing software used in this thesis. The fourth chapter-the practical attestation’s ambient vibration measures and its’ resonance periods analyses:first, tests the environmental vibration sources and measuring altitude’s influence on identifying resonance periods;second, studies the applicability of frequency resonance functions to identify the mixed construction historic building walls’ resonance periods, and if there is any difference between difference material location ’s resonance periods in the same wall;finally, establishes the resonance period data base of the walls in the Din Jin Ton. The fifth chapter is to describe the conclusion and proposals of the study. The cause of confusions on identifying the mixed construction historic building walls’ resonance periods is the interruption of input signals and output signals, the difficulty can be solved by the way of using the frequency resonance functions, filtered the interruption of vibration sources from the surface of the earth, thus the spectrum figures become single peak value, and can identifying the walls’ resonance periods rapidly.
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