博物馆文物的防震保护研究(二)——设防地震动输入及结构地震动反应

Research on protection from earthquake of the cultural relics hi museum (2)——Motion in put on fortify criterion and structural response

通过对上海及邻近地区地震危害性分析,结合地震研究工作结果,根据上海博物馆文物防震保护的具体要求,研究确定了该博物馆文物防震保护的设防水准及地震动参数。场地地震动输入峰值加速度水准确定为50年超越概率3％,地震动反应谱采用上海市标准《建筑抗震设计规范》(DGJ08-9-92)中给出的地震影响系数曲线(阻尼比0.05),并将输入峰值加速度调整为180gal。研究采用了目前通用的拟合反应谱的方法,通过拟合选定的地震动反应标准谱,合成了6条人造地震波时程曲线,拟合精度控制在相对误差不大于5％;同时结合上海市《建筑抗震设计规范》(DGJ08-9-92)中所附的一条强震记录,共同作为上海博物馆结构地震反应分析的输入地震动。又根据上海博物馆建筑的结构特征分析,结合建筑结沟动力特征的实测结果,通过采用层模型结构时程分析计算方法,计算并获得了在遭遇设防地震时,上海博物馆建筑物每一层的地震动反应,表明上海博物馆建筑各楼层的地震动反应具有明显的楼层放大作用。对各楼层地震动反应的统计分析,给出了上海博物馆建筑物每一层的地震动参数,以此可作为今后文物地震危害性分析,及研究设计隔震装置等防震措施的依据。

By analysis of the quake harm for Shanghai and its neighborhood area, combining the results in Shanghai area earthquake researth, according to the real requirements of the cultural relics protection from quake for Shanghai Museum, the fortify level and the motion parameters of the cultural relics protection from quake for museum have been studied and determined. The input acceleration peak level of the site motion input peak acceleration level be determined as the exceed probability 3 % by 50 years, the motion response spectra be adopted by the quake influence coefficient curve (damping ratio 0. 05) from the Shanghai architecture anti -seismic code(DGJ08-9 -92) ,and the motion input peak acceleration be adjusted to 180 gal. In this way,one side the enough safety be provided and another side the quake back- ground of Shanghai Museum building site be considered. Then here adopt the global method by fitting response spectra, ie. by fitting motion response standard spectra selected, synthesized 6 artificial wave time history curves. The fitting precision is to be controlled in 5 % about the relative error. These artificial quake wave histories have the same statistical characteristics, along with one real motion time history in the Shanghai architecture anti ~ seismic code (DGJ08 - 9 - 92) , as the input motion of the structural quake response analysis for Shanghai Museum building. Then according to the analysis of the structural characteristics for Shanghai Museum, combining with the real measurement to the building structure dynamics characteristics, the structure design parameters have been corrected. By the story modal structural time history analysis and computation method, computed and gained the quake motion response at the every floor in the Shanghai Museum building when it encounters the fortify quake. The computational results show that under the action of the fortify quake, the quake motion response is provided with obvious story amplify effect in the every story of the Shanghai Museum building. For the quake motion response by the computation to the every story, work out the statistical analysis and give out the motion parameters for the every story in the Shanghai Museum building. It can be as the basis for the cultural relics quake harm analysis, isolator system design and other protection methods future.