The Effect Of Ground Motion Intensity Index On Structural Nonlinear Response

With the wide application of performance based seismic design and seismic energy dissipation technology, it is important to choose and adjust actual acceleration records according to proper ground motion intensity index, especially for ensuring the seismic reliability of structure. Many scholars have done a lot of research for proper ground motion intensity index, and put forward many reference index. But, so far, it has no unified theory on which index should be used. Also, it has several disadvantages on these researches. For example, most of researches on correlations between ground motion intensity measures and structure responses choose two-dimensional model, this can reflect the response of the whole structure, but can't reflect partial response. Besides, with the different of structural nonlinear response,the period of structure is varied. Therefore, we aren't sure whether correlations between ground motion intensity measures and structure responses is same. Thus, There are still a lot of work need to complete. On the basis of summarizing predecessors' work, this article mainly do the following works:(1) Establish three-dimensional model structure based on OpenSEES and study the correlations between ground motion intensity measures and frame?frame-shear wall structure nonlinear responses under different period. The better the correlation is, the better ground motion intensity measure is. It will be more suitable to choose and adjust actual acceleration records, according to this ground motion intensity measure. Results show that among the three kinds of ground motion intensity index, the correlations between acceleration-related intensity index and structure responses under short period is best; the correlations between velocity-related intensity index and structure responses under medium and long period is best; the correlations between displacement-related intensity index and structure responses under long period is better.(2) Study the effect of peak ground velocity on frame and frame-shear wall structure nonlinear responses under different period. Results show that peak ground velocity can influence structure nonlinear responses under all kind of period. Within limits, with the increase of peak ground velocity, the responses of structure increase.(3) Study the effect of peak ground displacement on frame and frame-shear wall structure nonlinear responses under different period. Results show that peak ground displacement has no effect on short and medium period structure responses. It has an obvious influence on long period structure responses. With the increase of peak ground displacement, the responses of long period structure increase.