The Selection And Scaling Of Strong Motion Records

With the digital technical development of strong motion seismograph, strong motion observation has entered a new stage of development. In recent years, countries increased the range of earthquake station network layout, and received a large number of high-quality strong motion records. This makes the time history analysis method can be realized in practical applications. As advances in computer technology makes the time history analysis method can be applied in practical engineering. Time history analysis method are mentioned in the national codes, but for the time history analysis of how the input ground motion does not form a unified understanding. Nonlinear structural response is often highly sensitive to the selection and modification of input ground motions. In the past, there is few strong motion record, therefore we selected the well-known records (e.g. EL Centro) to analyze. A recurring challenge for practicing engineering is how to select and modify the ground motions for these nonlinear dynamic analyses.Foreign scholars began to study the method of the selection and scaling of strong motion records earlier, and get some results which could service the project. Although we have a large number of records, but we still use the well-known records. Many ground motion selection and modification methods have been proposed, but virtually no systematic studies exist that provide impartial guidance to engineers regarding appropriate methods for use in a specific analysis application. In this paper, five methods will be proposed, and use the best suitable method to select and scale the records of WenChuan and ChiChi earthquake. The paper compares some seismic design codes. It shows that there are obvious difference of the input of time-history analysis between the countries,The main work is:1.Development of the seismic design is along with the more knowledge we mastered. The key of the seismic design is the ground motion input. This article describes the development of the Earthquake resistant theory and the change of the input of earthquake ground motion.2.Due to the increase of available strong ground motion database, using and scaling real recorded accelerograms is becoming one of the latest contemporary research issues in this field. In this study, five methodologies for selecting strong ground motion time histories are discussed and summarized.3.This article uses the ANSYS finite element software to build three models.21 Horizontal acceleration records are selected and scaled by five different methods . And the scaled records are used to time-history analysis. the results shows the different scaling methods will lead to the different structure reaction. We use COV to compare the size of discrete of various methods.4.We get a lot of near-field acceleration records from WenChuan and ChiChi earthquake. In this paper, the records from WenChuan and ChiChi are divided into four categories according to Chinese code. The article selects 21 records which can best match design response spectrum. The best methods are the least squares and the method of Sa.5.This paper compares several specifications for the requirements of the input of the time history analysis, and selects some records to analyze by ANSYS.