A New Method for Calculating Earthquake Characteristics and Nonlinear Spectra Using Wavelet Theory

In the present study using the wavelet theory (WT) and later the nonlinear spectrum response of the acceleration (NSRA) resulted in estimating a strong earthquake record for the structure to a degree of freedom. WT was used in order to estimate the acceleration of earthquake mapping with equal sampling method (WTESM). Therefore, at first, the acceleration recorded in an earthquake using WTESM was studied in 5 levels. an‎d then for calculating the strong ground parameters (SGP) and the NSRA of the structure the filtered wave was used instead of using the main earthquake record (MER). The wavelet stages result in a more lenient filtered wave and it is better for calculating SGP and NSR because the noise is filtered. The method suggested for a large number of earthquakes was used and the results are detailed in the case of Kermanshah earthquake. Results show that in case of using WTESM, SGP error estimation would be less than 2% and the calculation error for NSRA would be less than 11%.