The Quantitative Relationship Between Earthquake Ground Motion And Structural Responses

The effects of the non-stationarity of earthquake ground motion on the structural responses is vital, but the quantitative relationships between them is hard to be estabilished, therefore, the research results of ground motion characteristics will not be widely used in engineering practice. Because the parameters describing the non-statioanrity of earthquake ground motion are large, and there exsits interaction effect among parameters, the calculation amount will be very large if we consider the whole combination of parameters simutaneously.Therefore,it is desirable to find ways to solve the problem. Based on the statistical analysis of the non-stationarity parameters of earthquake ground motion and their ranges of values, A DOE algorithm is proposed to study the non-stationary characteristics of ground motion intensity; And based on this DOE algorithm, parameter combination scheme with effect on structural response is obtained through multiple optimization of non-stationary characteristic parameters of ground motion. Finally, combinating with approximative technique, a proximate quantitative relationship model between the non-stationarity characteristic parameters of earthquake ground motion and structural responses will be established. The main results of this paper include the following aspects:(1)Based on more than ten thousand pieces of seismic acceleration records statistical analysis and survey of existing research results, given to reasonably describe the non-stationarity characteristics parameters of earthquake ground motion intensity and their ranges of values, And the design of experiments (DOE) method is introduced into the study, made suitable for ground motion parameters analysis of DOE method. The results show that the method can effectively reduce the amount of computation and it is possible to obtain better analysis results;(2)Based on orthogonal design parameters were analyzed, obtain the combination regimen of parameters and values, completing the variance analysis of characteristic parameters. The results show that the impact on the seismic response of structures more significant parameters will vary with the periodic and dynamic characteristics of structure; In comparison, the earthquake steady hold is more significant on the structure of the elastic or elastoplastic response; For periodic smaller structure, The effects of interaction between the characteristic parameters on the structural elastic response significantly, when the periodic become larger the effects of interaction between the characteristic parameters on the structural elastic response was not significant, but the impact on structural elastoplastic response is very significant.(3)We completed the combination regimen of parameters and values based on uniform design, Analysis the influence of the change of ground motion parameters on the structure of the elastic or elastoplastic response and obtained the trend of characteristic parameters vary with structural acceleration response and displacement response for the target parameters.(4)Combinating with approximative technique, a proximate quantitative relationship model between the non-stationarity characteristic parameters of earthquake ground motion intensity and structural elastic (elastoplastic) responses will be estiblished, the model can better reflect the relationship between different characteristic parameters and different structural dynamic response, and it provides the theory basis for engineering practice to setting up reasonable seismic characteristic parameters based on the structural characteristics and synthetic/select earthquake acceleration time history.