A study on the Relationship between Stiffness Reduction- Based Damage Index and Damage Degree for RC Buildings

結構損壞指標(Damage Index)為結構健康監測(Structural Healthy Monitoring, SHM)與損壞診斷評估之重要依據，一完善之損壞指標除能以量化數值顯示有無損壞之外，亦須能反映結構損壞輕重程度，方能作為結構安全警示及補強與否之決策依據。結構損壞後將產生勁度、強度與韌性折減，其中勁度反映於結構線彈性振動反應中，故許多損壞評估方法均以勁度折減為依據，然而目前尚未有完整研究探討勁度折減量與結構損壞程度之直接關係。 本文以Bouc-Wen非線性遲滯模式模擬鋼筋混凝土(RC)結構於反覆載重作用下勁度、強度、與韌性之衰減行為，針對純梁柱構架與含牆構架進行不同載重歷程之結構初始勁度分析，同時計算對應之Park與Ang損壞指標DIPA(1985)，以求得漸近初始勁度折減與DIPA關係曲線，再藉由損壞程度區分已定義完善之DIPA將勁度折減與損壞程度予以關聯。經由數值分析與實際載重試驗資料，本文提出RC結構有無含牆勁度折減與損壞程度之關係圖表，將可應用於勁度型損壞指標之損壞程度判定，使其更具務實應用價值。Damage Index is essential in structural health monitoring (SHM) and damage assessment. A decent damage index is able to detect the existence of damage and provide a quantified number along with a physical interpretation of damage degree. It can then be applied to the warning of structural safety and to the decision making of structural retrofit. Damage in structures induces the degradations of stiffness, strength, and ductility. Stiffness is the only parameter that can be extracted from the elastic vibration of structure. Thus, many damage assessment approaches are on the basis of change of structural stiffness. However, the damage degree corresponding to a certain stiffness change remains unclear. This thesis primarily investigates the relationship between the stiffness reduction and damage severity of RC structures for the decision making of stiffness-based damage assessment. In this study, the relation charts of stiffness reduction versus index DIPA by Park and Ang are established based on nonlinear structural response simulated by Bouc-Wen hysterestic model and cyclic loading test data of RC frames. Then, the damage severity corresponding to a specific stiffness-based-damage-index value can be determined according to the well-established damage classification of DIPA. Besides verification by numerical simulations and experimental data, the proposed method is employed to damage assessment of real buildings, which demonstrates its applicability in practice.謝誌..................................................i 中文摘要.............................................ii Abstract............................................iii 目錄.................................................iv 表格目錄...........................................viii 圖形目錄..............................................x 第一章 緒論...........................................1 1.1 研究動機與目的....................................1 1.2 文獻回顧..........................................2 1.2.1 損壞指標........................................2 1.2.2 非線性遲滯模式..................................4 1.3 本文內容..........................................6 第二章 結構損壞指標簡介...............................8 2.1 勁度型損壞指標SDI、ASDI[19].......................8 2.1.1 結構動態與特徵方程式............................8 2.1.2 層間損壞指標...................................11 2.2 位移型損壞指標DIPA...............................12 第三章 Bouc-Wen結構非線性變形遲滯模式................15 3.1 Bouc-Wen模式簡介.................................15 3.2 Bouc-Wen 模式參數分析及數值模擬..................17 3.2.1 形狀參數對遲滯圈之影響.........................18 3.2.2 強度折減與勁度折減參數對遲滯圈之影響...........19 3.2.3 擠壓效應對遲滯圈之影響.........................19 3.3 RC結構之非線性遲滯模式行為.......................20 3.3.1 有無牆體之構架遲滯特性.........................20 3.3.2 不同韌性之構架遲滯特性.........................22 第四章 勁度折減與DIPA損壞指標之關係..................24 4.1 結構初始勁度折減與DIPA...........................24 4.1.1 結構初始勁度之萃取.............................24 4.1.2 不同載重進程之DIPA計算.........................25 4.1.3 結構初始勁度折減與DIPA之關係曲線計算流程.......26 4.2 RC結構初始勁度折減與DIPA之關係曲線...............29 4.2.1 有無牆體之影響.................................29 4.2.2 不同韌性之構架之影響...........................31 4.3 Bouc-Wen模式參數變異之影響.......................32 4.3.1 形狀參數之影響.................................33 4.3.2 強度折減與勁度折減參數之影響...................33 4.3.3 擠壓效應、βd與Δu,mon之影響...................34 4.4 四種RC結構之初始勁度折減與損壞分類...............36 4.5 依據結構反覆載重試驗資料進行驗證.................37 4.5.1 反覆載重試驗簡介...............................37 4.5.2 勁度折減與DIPA關係計算流程.....................38 4.5.3 結果比較與驗證.................................38 第五章 RC結構震後健康診斷............................40 5.1 數值模擬.........................................40 5.1.1 非線性結構模式之弱震與強震反應模擬.............40 5.1.2 線彈性系統之參數識別...........................41 5.1.3 ASDI損害診斷...................................42 5.2 實測RC結構分析...................................43 5.2.1 結構簡介.......................................43 5.2.2 受震前後系統參數識別...........................44 5.2.3 損害診斷分析...................................46 第六章 結論與建議....................................49 參考文獻.............................................51 表格.................................................56 圖形.................................................7