應用微地動量測探討中小學校舍補強前後穩定性之研究

Investigation of the Stability of Pre-retrofitted and Postretrofitted School Buildings by using Micro-tremors

張健財

希爾博特黃轉換 ； 內隱模態函數 ； Hilbert Huang Transformation (HHT) ； Intrinsic Mode Functions (IMF)

萬能學報

35期（2013 / 07 / 01）

213 - 220

繁體中文

本研究針對在中小學校舍補強前後之建築物做微地動量測，分別針對中小學校舍補前與補強前與補強後，分別以微地動量測學校建築物之振動訊號。研究期間到現地量測中小學校舍補強前或補強前後之振動特性，以觀測中小學校舍補強前後所產生之振動特性對中小學校舍補強前後安全性之影響。研究補強方法對校舍穩定性提升之效果。經由量測學校建築震動現況，用以研判中小學校舍補強前後中小學校舍補強前後是否有異常狀態發生，作為中小學校舍補強前後。本研究將由微地動儀所測得的中小學校舍補強前後訊號資料，以希爾博特黃轉換（HILBERT HUANG TRANSFORM,HHT）之內隱模態函數（Intrinsic Mode Functions IMF），經對比後，在東西及南北之差異數皆為二個內隱模態，上下振動方向之內隱模態數在補強前後不變。據此可推論校舍補強後的振動特徵值有顯明的變化。校舍補強後可確保中小學校舍補前後穩定性，並對校舍耐震能力有作有效提升。

Using of these data collected by micro-tremor, evaluation of the safety of pre-retrofitted and post- retrofitted school buildings is performed. Here the the Hilbert Huang Transformation (HHT) technique will be used to identify intrinsic mode functions IMFs of school buildings under different retrofitted stages that signals were measured at different stages when retrofitted construction were under constructions. The information observed can be referred as guidelines to judge the stability of the pre-retrofitted and post- retrofitted school buildings and to ensure stability of the pre-retrofitted and post- retrofitted school buildings. There are two extra IMFs in the East and West components in pre-retrofitted compared with postretrofitted school buildings while there is no difference in the Up-down Component in the implicit mode.

1. Chang, J.T.(2009).Chang, J.T., A Simple Object Oriented Program for Fast Fourier Transformation of Signals, Hilbert Huang Transform, Wiener Filter, and Horizontal to Vertical Spectral Ratio of Signals in Microsoft Windows XP system,” Lecture Notes, Vanung University, Chung Li, Taoyuan, Taiwan.; 2009..
2. Huang, Norden E.,Wu, M.C.,Long, S.R.,Shen, S.S.,Qu, W.,Gloerson, P.(2003).A confidence limit for the Empirical Mode Decomposition and Hilbert Spectral Analysis.Proceedings of the Royal Society of London,459,2317-2345.
3. Huang, Norden, E.,Shen, Z.,Long, S. R.,Wu, M. C.,Shih, E. H.,Zheng, Q.,Tung, C. C.,Liu, H. H.(1998).The Empirical Mode Decomposition and the Hilbert Spectrum for Nonlinear and Nonstationary Time Series Analysis.Proceedings of the Royal Society of London,454,903-995.
4. Nakamura, Y.(1989).A Method for Dynamic Characteristics Estimation of Subsurface Using Microtremor on the Ground Surface.Quarterly Report of Railway Technical Research Institute (RTRI),30(1)
5. Nakamura, Y.(1997).Seismic Vulnerability Indices for Ground and Structures Using Microtremor.World Congress on Railway Research,Florence, Italy:
6. Nakamura, Y.、Saito, A.(1983)。Estimations of Seismic Response Characteristics and Maximum Acceleration of Surface Ground using Strong Motion Records。Proc. 17th JSCE Earthquake Eng. Symposium