Research On Frequence Domain Method For Calculatting Site Execellence Period Based On Stratigraphic Information

The site excellence period refers to the period value of a harmonic component of the seismic wave when it resonates with the foundation soil layer.It is an important parameter for the classification of the site and the seismic design of the structure.At present,there are two main types of methods for determining the excellence period of a site.One is the field measurement method using observation instruments,and the other is the calculation method based on stratum information.The former has strict requirements on the selection of measurement instruments and observation points.and is easily affected.The site conditions are limited,and the latter has problems such as low calculation accuracy or too complicated calculation process.The impulse response spectrum method is a more accurate method for calculating the site's remarkable period based on the formation information calculation method,and it also has similar defects and deficiencies.For this reason,this article uses the transfer matrix method to improve the impulse response spectrum method,and proposes a simpler,more efficient and more tolerant frequency domain impulse response spectrum method,and based on this method,it is important to achieve site excellence.The intelligent extraction of cycles was studied.The frequency domain impulse response spectrum method proposed in this paper takes the elastic layered half-space one-dimensional wave problem as the site calculation model,uses the Fourier spectrum of the pulse wave as the source input,and calculates the source component of each period according to the transfer matrix method.In order to establish the relationship between the site response and the source period,the period corresponding to the maximum value of the site response is the superior period of the site,and the maximum value is the basic superior period of the site earthquake wave theory to determine the superior period parameters of the site.On this basis,in order to achieve the goal of extracting the excellent period without manual intervention and completely determined by the computer to determine the control parameters,the method of automatically determining the control parameters by the computer is studied,the implementation process is designed,and the relevant MATLAB program is compiled.A number of engineering examples have been calculated and analyzed,and the correctness of the program has been verified by comparing the calculation results obtained under different methods.In this research work,the following points can be learned:(1)The frequency domain impulse response spectrum method has more advantages in the calculation method;(2)The frequency domain impulse response spectrum method requires fewer control parameters;(3)The frequency domain impulse response spectrum method effectively eliminates the Gibbs effect;(4)the frequency domain impulse response spectrum method no longer needs to set a window function;(5)the frequency domain impulse response spectrum method is more conducive to the realization of intelligent calculation.