Period equations provided by seismic codes are generally derived by calibration with recorded period data of buildings located in high seismicity regions. These period-equations do not account for either the design level of seismicity or the permissible limit of lateral drift. Buildings designed under high level of seismicity are expected to display higher stiffness and shorter periods than buildings designed under low-to-medium seismicity levels. In addition, buildings designed with high level of permissible lateral-drift are expected to display lower stiffness and longer periods than buildings designed with low level of permissible lateral-drift. In this study, the theoretical fundamental-periods of an ensemble of regular reinforced concrete (RC) and steel moment-resisting frame (MRF) buildings having 3-, 6-, 9- and 12-stories and designed with various levels of seismicity and permissible lateral-drift are evaluated. The obtained outcome indicates the sensitivity of the MRF theoretical-periods to the design seismicity and the permissible lateral-drift. The results also indicate the need for modifying the current period equations to realistically account for the variations in the design seismicity and allowable lateral-drift of MRF buildings.

中文翻译：

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在可变地震烈度和允许漂移的条件下设计的框架建筑物的理论周期特性

由地震代码提供的周期方程通常是通过对位于高地震活动地区的建筑物的记录周期数据进行校准得出的。这些周期方程式既不考虑地震的设计水平，也不考虑横向漂移的允许极限。与在中低地震等级下设计的建筑物相比，在高地震等级下设计的建筑物预计将显示更高的刚度和较短的周期。此外，与设计水平允许的水平漂移较低的建筑物相比，设计水平允许的水平漂移较高的建筑物预计会显示出较低的刚度和更长的周期。在这项研究中，常规钢筋混凝土（RC）和抗弯框架（MRF）建筑由3、6，评估了9层和12层的结构，并设计了不同级别的抗震性和允许的横向漂移。获得的结果表明了MRF理论周期对设计地震活动性和允许的横向漂移的敏感性。结果还表明需要修改当前周期方程，以切实考虑MRF建筑物的设计抗震性和允许的侧向漂移的变化。