博物館展示品之耐震性能評估

Evaluation of Seismic Resistance of Artifacts in Museums

A series of shaking table tests had been conducted on the artifacts in museums to evaluate their seismic response while fixed with different protection methods. Paintings, scrolls and vases, which were seriously damaged in the past earthquakes, were tested in a model room with a plane dimension of 8m by 5m, and 3.5m in height. Two types of isolators was examined under various levels of seismic loadings to exam their performance for protecting artifacts. Test results indicated that providing wax at the corner of the paintings was effective to prevent the crash or dropping under the vibration of the earthquake. Wires and wax were able to enhance the seismic resistance capacity of vases up to acceleration of 1500gal. When the isolator placed at the bottom of the showcase, the horizontal acceleration at top of the isolator was reduced to less than 100gal from 800gal of the input wave. When the isolator was placed in the showcase, the performance was reduced due to the rocking behavior of the show case. Rocking of the showcase caused over 1000gal response on the top of the isolator. 博物館中的展示品如吊畫、捲軸、花瓶等在過去的大地震中發生不少損壞。本研究乃以振動台實驗測試展示品在現有的展示及固定方式下之耐震性能，實驗在一安裝於振動台上，高、長、寬分別為7、5、3 公尺的鋼構模型房屋中進行，並同時測試了兩種應用於展示物防震之隔震器在不同地震強度下的隔震性能。實驗結果顯示若在吊畫邊框四角的背面使用蠟與牆面固定，可以有效避免在過去地震中常見的擺動、碰撞與掉落等行為造成的破壞。使用釣魚線以及蠟等常見的固定方式，可使花瓶等展示品在1.5g加速度下仍未傾倒。當隔震器安裝於展示櫃底部時，隔震器可將800gal的水平輸入加速度降低至100gal以下，然而當隔震器安裝於展示櫃內部時，展示櫃在地震中的擺動以及移動行為將會大幅降低隔震器的性能，實驗發現當展示櫃擺動時，內部隔震器上端的加速度達到1000gal，對其上端的展示品構成不小威脅。