應用子空間識別法於長期結構物之地震反應解析

Application of Subspace Identification Technique to Long Term Seismic Response Monitoring of Structures

林珮涓(Pei-Chuan Lin)

指導教授 ： 羅俊雄

國立臺灣大學/工學院/土木工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.02665

摘要

本研究的目的在於探討子空間識別法(Subspace Identification)於結構物之系統識別，配合中央氣象局對結構物地震反應所進行之強地動觀測計畫，選擇七棟建築物及一座核電廠圍阻體縮尺模型，針對所收集到之地震反應進行分析，探討及比較不同地震反應下該結構物動態特性之差異，並根據實際的分析結果來發展適合用於國內之耐震設計規範。首先，根據使用資料的類型將子空間識別法分為兩種並介紹各自的理論推導：(1)單獨以輸出資料為基礎進行系統識別的隨機子空間識別法(Stochastic Subspace Identification, SSI)，其分析時所使用的資料為微震資料；(2)以輸入及輸出資料為基礎的子空間識別法(Subspace Identification, SI)，其使用資料為地震時所記錄到的地表加速度歷時與結構反應。本文依據不同樓層高度及結構特性，選擇六棟已安裝強震儀之一般建築物、一棟含中間層隔震系統的特殊建築及一座核電廠圍主體縮尺模型，利用子空間識別法分析地震記錄，探討子空間識別法參數的設定及探討結構物在地震作用下的動態特性。並於最後將分析結果的第一個自然震動頻率與國內耐震規範中所建議的經驗公式相比，期望提供一條更接近真實結構物的建議公式。另外，對於含中間層隔震系統的特殊建築，將探討隔震層在地震下對結構的影響及其作用行為。

關鍵字

隨機子空間識別 ； 子空間識別 ； 系統識別 ； 中央氣象局結構物強震監測網 ； 中間層隔震系統

並列摘要

This study applies the subspace identification to system identification. Base on the Central Weather Bureau Taiwan Strong Motion Instrumentation Program (TSMIP) seven instrumented buildings and one 1/4 scale-down nuclear plant containment structure as the target structures for the analysis. Based on the collected seismic response data during the past, each event data will be analyzed to identify the dynamic characteristics of the structure during earthquake excitation. The result of analyses are in order to develop the proper earthquake-proof design norms for architectural structures in Taiwan. First, according to the use of the collection data two theoretical derivations are introduced：(1)the stochastic subspace identification(SSI) using output-only data, or the ambient vibration data for continuous monitoring；and (2)the subspace identification (SI) using input/output data, or the seismic responses. In this study, there are six normal steel or reinforced concrete buildings with different height, one mid-story isolation building, and a 1/4 scale-down nuclear plant containment structure are analyzed by using Subspace Identification. In order to study the parameters used in the analyses and discuss the change of structural properties during earthquake excitation. In the end, comparing the first natural frequencies from the system identification with the values which are suggested in internal earthquake-proof design norms. Hope to propose a new regression line that can have the best estimation between the height and the first natural frequencies. Furthermore, the effect of the isolation system and the dynamic characteristics will also be discussed in this study.

並列關鍵字

Stochastic Subspace Identification ； Subspace Identification ； System Identification ； Central Weather Bureau Structure Strong Earthquake Monitoring System ； Mid-isolation system

參考文獻

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