natural limitation period自然时效
natural pitching period纵摇固有周期
natural death period自然病程
natural vibration period自振周期
natural l period固有周期
natural synoptic period[气候] 自然天气周期;自然综观期;自然天气周期
natural rolling period横摇固有周期
natural dormancy period自然休眠期
basic natural vibration period基本自振周期
The concept of isolation is to prolong natural period and provide higher damping level to traditional structure to avoid resonance with the relatively short period components dominant in earthquake ground motions.
隔震通过延长结构自振周期、增加阻尼而避免与短周期为主的地震发生共振。
参考来源 - 组合隔震与三维隔震（振）理论及试验研究