| It has been paid much attention by anti-seismic engineering circles since anti-seismic design methodology based on energy was proposed. As a comprehensive index in assessing the properties of ground motions and the anti-seismic performance of structures, considering energy as an element in anti-seismic design plays an active role in improving anti-quake theories. The choice of inputting ground motions has a direct impact on structural response regardless of anti-seismic design method. Thus, researches on anti-seismic design methodology gives priority to inputting ground motions, as well as in anti-quake design method based on energy. A large number of achievements of input of ground motions were obtained in existed researches, most of which chose seismic waves based on response spectrum. However, seismic waves with same or similar response spectrums may differ significantly in energy properties, so it is urgent to establish a method based on energy classification to input ground motions.Influence of ground motions with different energy scale on structural response was studied in this paper, in different groups of ground motions divided on the basis of intensity attenuation rule and by measurement index of energy. To achieve goals above, main works and conclusions are as follows:①Groups of ground motions divided by intensity attenuation rule.According to intensity index, a research method based on the rule of intensity attenuation was proposed in this paper and a database was created by different groups of ground motions divided by relationship of intensity, magnitude and transmission distance. On the basis of that, value ranges in group for earthquake magnitude and epicentral distance in one site condition and one rule of intensity attenuation were determined to obtain the relation of intensity and energy.②Choosing input of ground motions based on energy analysisPseudo-velocity spectrum by Housner was chosen as a primary index for energy classification, and the impacts of other index like PGA, energy duration, Arias strength and energy flux on pseudo-velocity spectrum curves were referred to. Rules of energy’s change with magnitude and transmission distance in an area with one intensity, as well as rules for grading in different intensity zones. Energy in inputting ground motions shows scales with intensity’s change and wave choosing method based on pseudo-velocity spectrum in different intensity zones was proposed in this paper. ③Verification and evaluation on wave choosing method in this paperRules of intensity attenuation in reference zones in Chinese Codes were chosen in this paper and set zone of7degree0.1g as an example to verify corresponding relationships between wave choosing method in codes and in this paper, according method of choosing waves by total spectrum and part spectrum. Four groups of ground motion records were acquired by three wave choosing methods above and input structures to analyze elastic and plastic history. Storey shear, inter-storey displacement and energy dissipated through plastic under the three groups of records were compared.According to the approach in this paper, structural elastic and plastic response caused by ground motions graded by magnitude in one intensity zone had the less discreteness. That means wave choosing method based on energy has response grading and energy grading in structural response and implies that choosing wave based on energy corresponds with structural response. In design, ground motion input can be selected reasonably according to the scale of energy that may be dissipated in structures, in order to ensure energy can be dissipated in different scales.At the end, disadvantages and points that need further research was pointed. |
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