2018年0206花蓮地震造成大量結構物受損，而非結構物震損也不容忽視，以花蓮國軍醫院進豐門診處為例，因近斷層效應下較大瞬時位移、地表速度，使院內多項非結構物傾倒，如藥品冰箱、水塔和病例櫃等；結構物雖無明顯損壞，醫療功能卻暫時停擺。此類震損於國內外層出不窮，因此本研究針對無固定之非結構物在近斷層震波下轉動行為，藉由實驗驗證已知理論公式，並經過簡化後提出適用於對稱、非對稱剛體傾覆模型，以判斷在工址設計反應譜下非結構物是否需加固以防傾倒。
本研究以剛體自由擺動實驗，驗證Housner(1963)理論中剛體運動方程式，結果顯示非對稱剛體也符合Housner運動方程式；以振動台傾覆實驗驗證Nabeshima(2016)理論中傾覆限度解析解，並確認其假設符合實驗結果。
各傾覆限度理論於使用上皆有不同限制，為建立一較簡易傾覆判斷方法，本研究根據理論、實驗結果進行適當簡化假設，將小擺角下重力造成力矩假設為定值，並忽略碰撞、摩擦能量散失，並將近斷層震波簡化為單週期弦波。假設對稱、非對稱剛體在無擺動或擺動一次後傾倒，由邊界條件、能量守恆原理，提出簡化傾覆限度模型。
最後將簡化模型輸入Excel軟體，建立傾覆限度計算表，可由已知剛體幾何條件，自動計算多種頻率單週期弦波下剛體傾覆限度。將簡化模型結果與其他傾覆理論以及多組對稱、非對稱試體傾覆試驗結果比對，確認其具有一定可靠度。此一簡化模型僅需量測剛體重心位置，即可判斷浮置剛體於工址反應譜下是否有傾覆可能。

Based on the experiences learned from earthquakes, it is recognized that the losses to the non-structural component can be significant. This study aims to identify the overturning limit of free-standing rigid bodies. A numerical solution on the input level of one-sine pulse as a substitute of a near-fault ground motion is derived for the overturning of rigid bodies. Based on the rigid blocks rocking and overturning experiments, rocking moment of gravity can be reduced to time-invariant parameter. This enables us to avoid the computation of complicated differential equation. By the conservation law of angular momentum and the conservation law of mechanical energy, the overturning limit of certain geometric shape under vary frequency ground motion can be defined. Import the simplified formulation into excel spreadsheet to build a numerical model, which calculates and plots overturning limit automatically.

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