The Research On Selection And Adjustion Of Ground Motion Records In The Time-history Analysis

In recent years,performance-based seismic design has received more and more attention in engineering field and has played an important role in earthquake disaster prevention and mitigation, and protecting life and property safety. Time-history analysis is the main method of performance-based seismic design,and at the same time the ground motions selected and adjusted is the key step of time-history analysis, thus the ground motions selected and adjusted become an important topic in seismic design.First of all, the field characteristic parameters and the parameters of the seismic wave frequency spectrum were combed, summarized and summed up, and the significance and method of theirs were given the precise definitions. In the below paper, the parameters were applied in the ground motions selected and adjusted. The seismic response spectrum theory was described in detail in the paper, aiming at the restrict bottleneck of the time-history analysis development, and a system and effective method of the input seismic wave selecting was given mainly based on seismic response spectrum, with seismic amplitude, duration, characteristic period as the wave selection index. The programs of the screening method were developed by MATLAB language. That, the ground motions selected were suitable in elastic time-history analysis, was proved by the high-rise frame-tube building engineering example.Secondly, the insufficiency of a current input seismic wave method was pointed out in this paper by the engineering example. At the same time the force and displacement index showed that the result difference was very big between this method and the normal seismic wave input method, thus the conclusion, that the input method was not suitable for the elastic time-history analysis, was drawn. In this paper the impact, which was produced by the large seismic amplitude adjustment of ground motions, on the characteristic period and energy was analyzed.Finally, in this paper based on the wavelet transform theory, the adjustment programs to process the input ground motions were written by the MATLAB language. Then the target, that making the input ground motions suitable for practical engineering analysis, was realized.