场地条件对竖向抗震设计反应谱最大值的影响

Effect of site condition on maximum value of vertical seismic design response spectrum

文章采用294条竖向按我国相关建筑抗震设计规范划分场地条件的强震记录反应谱,提出用有效峰值加速度(EPA)表示地震动强度,按照Ⅱ类场地上EPA进行分组,研究每个分组区间场地条件对竖向反应谱最大值的影响。结果表明:同一地震动强度下,随着场地变软,竖向场地系数随之增大;同一场地条件下,随着地震动强度提高,竖向场地系数有减小的趋势。通过计算与分析,给出了不同类别场地竖向设计反应谱最大值的1组竖向场地系数建议值。

The records of 294 vertical strips of actual strong earthquake response spectrum are classified by the current site categorization criteria of the related code for seismic design of building in China . The ground motion intensity is represented by the effective peak acceleration （EPA） and classified by EPA on the site of Class Ⅱ ,and then the effect of site condition on the maximum value of vertical re-sponse spectrum at each site is studied .The results show that in the same ground motion intensity , the vertical site coefficient increases with the increase of weakness of the site ,while in the same site condition ,the vertical site coefficient has a tendency to decrease with the increase of the ground mo-tion intensity .By the analysis of numerical results ,a group of vertical site coefficient corresponding to the maximum value of vertical design response spectrum at various sites is proposed .