狀態空間DLV法在扭轉耦合結構之地震損傷探測試驗研究

Abstract

本研究以DLV損傷探測法結合SRIM系統識別分析，針對扭轉耦合結構進行一系列數值模擬與振動台試驗。數值模擬結果顯示，不論結構為單一或複數樓層受損，均可準確定位出破壞樓層。在振動台試驗方面，分別考慮以位形空間DLV法與狀態空間DLV法進行結構損傷探測分析。結果顯示位形空間DLV法之偵測能力不佳，狀態空間DLV法則有較高之成功率，初具實際應用之潛力，惟仍有部分案例未能準確定位，應與試驗之地震強度較低(PGA=0.05g)有關。由於監測訊號中含有雜訊，當擾動訊號較弱時，噪訊比相對較高，系統識別誤差因而增大。此外，當破壞定位向量經由柔度差異矩陣之奇異值分解得到後，需加載於健康結構上進行應力分析。本研究目前採用之ETABS模型與真實結構間仍有落差，故導致額外誤差。建議未來應由系統識別參數進行應力分析，進一步提升實務應用之可行性。

In this study, method of damage location vector (DLV) in conjunction with SRIM system identification is developed for damage detection of torsionally coupled structures. It is verified via a series of a series of numerical simulations and shaking table tests. Simulation results indicate that the damaged stories can be accurately identified, regardless of single or multiple damages. The experimental data have been analyzed using both the configuration-space DLV and state-space DLV methods for damage detection. Results show that the configuration-space DLV method fails to identify the damage in most cases while the state-space DLV method proves more successful, indicating its potential in practical application. Nevertheless, there were still a few cases not accurately identified. It is partly attributed to the low earthquake intensity (PGA=0.05g) considered in the tests as the noise-to-signal ratio becomes higher for weak signals, thus introducing errors in the system identification as a consequence. Moreover, the damage locating vectors obtained from singular value decomposition of the flexibility differential matrix are to be applied on the intact structure for further stress analysis, and discrepancy between the ETABS model and test structure considered in this study leads to additional errors. In order to be practically more feasible, it is suggested to further explore new methodologies for stress analysis using parameters directly from system identification.