The Effect Factors And Uncertainty Analysis Of Ground Motion Characteristic

This thesis collected about ten thousand earthquake records, and the records aremainly from Euro databank, American databank and Taiwan's network and some ofthem are from others country or regions. The records are sorted by magnitude,epicenter distance, site classification or fault mechanism as well according to theresearch objectives. Based on grouped data, detailed statistical analyses have beendone for strong ground motion characteristics from different aspects. In addition, thethesis also researches the effects of site classification and fault mechanism uponground motion characteristics. Finally, the thesis analyses the uncertainty of groundmotion and its effect factors.The thesis pick up 163 groups strong ground motion records from Euro databankand analyses its statistical features of amplitude envelope line. The symmetry of plusand minus direction envelope line and the difference among three-componentenvelope lines was emphasized and concerned. From the statistical results, it can beseen that the envelope line is asymmetrical, and the smoothness degree of theconfiguration of envelope line of plus and minus direction is different too. However,the envelope line can be represented by single peak curve commonly. About threecomponents envelope lines, the horizontal amplitude are all more than itscorresponding vertical component; the station of peak of vertical component is moreclose to y-axis, this means that climb speed of vertical component envelope line isfaster compared horizontal component; and that the shape of horizontal envelope lineis wider and flatter.Based on the 156 groups of earthquake bedrock recordings, those are mainly fromWestern US, China Taiwan and so on. The thesis mostly researches the crossing-zerorates of strong earthquake acceleration records, and uses them to reflect the frequencynon-stationary features. Furthermore, we utilize the time interval between neighboringpeak point to reflect the frequency non-stationarity incorporating the effect of ripplesand make comparisons with the corresponding results by using the crossing–zeromethod. The results of analyses and comparisons indicate that the crossing-zero ratescan reflect the frequency non-stationary features to certain length. It is noticed that thepredominant frequency has a role of control in structure response, the thesis alsoanalyze the time-variable characteristics of the predominant frequency, compared withthe crossing-zero rates, and find out that the fluctuating feature is more obvious inthis case.According to the epicenter distance and the site classification, the thesis sorts 404groups of earthquake recordings of the main shock, chi-chi earthquake China Taiwanin 1999. Based on these data, the statistic properties of duration, PGA, envelopes, andresponse spectra ratio of horizontal and vertical component of the accelerationrecordings have been studied. The duration of horizontal components of accelerationrecords increases as site condition becomes softening. The direction of fault slip has...