Effects of soil structure interaction on the response of building during the strong earthquake ground motion, 1986

The analysis of the effects of soil-structure interaction on the response of structures during strong earthquake ground motions are presented. The possibility of estimating the rocking motion of the foundation is examined through geometrical analysis of recorded motions. The records obtained during the San Fernando and the Lytle creek earthquakes are utilized to estimate the rocking of the foundations of Millikan Library as well as the translation of the building at the roof relative to a moving frame of reference attached to the foundation. Through these estimates and using the appropriate transfer functions the modal frequencies of the structure and those of the complete soil-structure system are identified.; An experimental approach for estimating the impedance functions of the foundation is explored and the horizontal and rocking compliances are estimated for the foundation of Millikan Library. Comparisons of the results with those obtained from analytical studies are presented.; The possible contribution of the hysteretic damping to the response of a simple mathematical model of a soil-structure system is examined. The response of Millikan Library to the forced-vibration testes is used to test the model through an attempt to reproduce the experimental observations.

本文阐述了强地震动作用下土-结构相互作用（soil-structure interaction）对结构响应的影响分析。通过对实测地震动记录开展几何分析，研究了估算基础摇摆运动的可行性。本次研究采用圣费尔南多（San Fernando）地震与莱特尔溪（Lytle Creek）地震期间获取的实测记录，对米利肯图书馆（Millikan Library）的基础摇摆运动，以及建筑屋顶相对于固连于基础的移动参考系的平动位移进行了估算。基于上述估算结果并结合恰当的传递函数（transfer functions），识别得到了结构自身的固有模态频率以及完整土-结构体系的固有模态频率。
本文探索了一种估算基础阻抗函数（impedance functions）的试验方法，并针对米利肯图书馆的基础估算得到了其水平与摇摆柔度；同时将该方法所得结果与解析研究结果开展了对比分析。
此外，本文研究了滞回阻尼（hysteretic damping）对土-结构体系简化数学模型响应的潜在贡献；并借助米利肯图书馆的强迫振动试验结果，尝试复现试验观测现象以验证所提出的模型。