考慮地盤種類之隔震黏滯阻尼比最佳化設計公式

Optimal Design Formula for Viscous Damping Ratio in Isolation System with Consideration of Site Classification

楊卓諺(Cho-Yen Yang) ； 范揚志(Yang-Chih Fan) ； 鍾立來(Lap-Loi Chung) ； 陸寶軍(Bao-Jyun Lu)

《結構工程》 32卷1期 (2017/03) Pp. 71-99

https://doi.org/10.6849/SE.201703_32(1).0004

摘要

本文旨在探討隔震系統輔以黏滯阻尼消能之最佳阻尼比，系統之回復力與阻尼力皆為線性。因前人所用之地表加速度為白雜訊，並未顯現出台灣地盤之特性，故本文以台灣177 個地震紀錄作為地表加速度。並將結構物分成剛體結構與非剛體結構，非剛體結構再以無阻尼以及含阻尼作為劃分。再來根據結構的分類表建立運動方程式，利用狀態空間法以數值模擬求得不同結構參數與地盤種類的動力反應。藉由變化阻尼比，使上部結構絕對加速度反應最小之阻尼比即為最佳阻尼比，進一步利用這些參數與對應之最佳阻尼比迴歸出設計公式。最後以實際案例比較前人與本文提供之公式的優劣，並且證明本文的設計公式之可行性，且有效反映地盤特性對阻尼需求之影響，可作為隔震設計之實務應用中，決定阻尼大小之參考依據。

關鍵字

設計公式 ； 隔震 ； 黏滯阻尼 ； 最佳化 ； 地盤

並列摘要

In this paper, the optimal viscous damping ratio for isolation system is studied. The linear restoring and damping force are considered. According to the previous literature in optimal design formulas, the white-noise excitation is considered. However, the case analysis in previous study was not doing well because the formulas could not retain the regional feature. Therefore, the numerical analysis intended to input several ground motion records in Taiwan. After that, the rigid and non-rigid superstructures for isolation system with various structure parameters are numerically simulated. The root mean square of absolute structure acceleration is selected to be the objection function for obtaining optimal isolation damping ratio. Repeating the optimal process with various structural parameters, the proposed simple design formula was developed by regression of those optimal isolation damping ratios from numerical simulations. Finally, we conducted the case analysis to verify the feasibility of proposed optimal design formulas.

並列關鍵字

design formula ； isolation ； viscous damping ； optimal ； site classification