摘要
为保护馆藏浮放文物,采用振动台试验方法,研究了地震作用下,基于不同陈列柜边界条件下的文物摇晃响应,其中陈列柜的高宽比较小。根据某博物馆展柜原型,制作了1∶1比例模型,并在模型内浮放铜质文物。分别考虑陈列柜底部浮放及固定于振动台面,进行了振动台试验。通过白噪声激励,获得了两种边界条件下陈列柜的基频;通过对模型分别输入EL-centro波、Taft波及Ⅱ类场地人工波,并考虑加速度峰值分别为0.1g、0.2g、0.4g、0.7g,研究了地震作用下陈列柜及文物的震害形式,对比分析了两种边界条件下典型节点位移及加速度响应。结果表明:无论陈列柜处于固定还是浮放状态,其基频远大于地震波卓越频率,因此震害较轻;对浮放文物而言,地震波强度较小时,不同条件下文物的摇晃响应为:陈列柜浮放>陈列柜固定条件;地震波强度较大时,由于陈列柜与振动台面的摩擦减震作用,文物的摇晃响应为:陈列柜浮放<陈列柜固定条件。因此,为减小文物的摇晃响应,高宽比较小的陈列柜宜以浮放形式为主,并保持适当的间距。
To protect movable cultural relics,seismic responses of museum free-standing cu ltural relics were studied considering different boundary conditions of showcase with low ratio of height against width by shaking table tests.Based on actual sizes of a museum showcase,a 1∶1 scale model was built.A bronze cult ural relic was put in the showcase by free-standing mode.Shaking table tests we re carried out considering 2 boundary conditions of showcase bottom: fixation an d free-standing status.Excitation frequency distributions of the showcase unde r both boundary conditions were obtained by white noise;seismic response of bot h showcase and relic were studied by inputting 3 different types of earthquake w aves(El-centro wave,Taft wave and Artificial wave of II type site classificati on) with different intensities(0.1g,0.2g,0.3g and 0.7g of peak ground a cceleration values).Results show that whether the showcase is in fixation or fr ee-standing status,its prominent frequency ingredients are far greater than th ose of the input earthquake waves,thus the showcase is not damaged seriously;f or the relic under free-standing showcase boundary condition,compared to that of fixation condition of showcase,its oscillation response is more serious unde r low intensity of earthquake,while much slighter when earthquake intensity inc reases obviously because of friction between showcase and shaking table.Museum showcases with low ratio of height against width are better free-standing for m itigating oscillation response and keep some distance.
出处
《土木工程与管理学报》
2011年第3期401-406,共6页
Journal of Civil Engineering and Management
基金
文化部科技创新项目(17-2009)
关键词
陈列柜
边界条件
浮放文物
摇晃响应
振动台试验
showcase
boundary condition
free-standing cultural relics
oscillation response
shaking table tests