摘要
以西安小雁塔结构为原型,对其缩尺比例为1/8的砖塔模型进行了振动台试验。模型采用旧青砖和糯米汁灰土浆作为砌筑材料以还原古代砖塔的营造特点,试验分析了结构模型在多遇以及罕遇地震烈度水平下的损伤状况、加速度响应,位移响应和层间剪力分布,并通过分析各层测点在白噪声激励下的频率响应函数,得到了结构动力特性及其变化规律。试验结果表明:模型结构鞭鞘效应明显,损伤主要集中在顶部,其破坏形态与类似结构的实际震害特点一致;在不同的地震波作用下结构响应不尽相同,其加速度位移与结构当前频率、地震波频谱特性息息相关;随着地震波加速度峰值的增大,模型一阶频率减小了27.4%,阻尼增大为2.55倍,地震加速度放大系数减小;在8度多遇地震作用下,模型结构的顶层层间位移角达到1/116,结构已达到严重破坏状态,对处于高设防烈度地区的类似古塔应采取保护措施。
A shaking table test was conducted on a 1/8 scaled model of Xi’an Xiaoyan Pagoda.The material used in the model is the old brick and mortar of sticky rice juice.The damage,acceleration response,displacement response and the distribution of shear force in the structural model under the excitation of multiple encounters and rare earthquakes were analyzed.The dynamic characteristics were identified through analyzing the frequency response function at each measurement point under a white noise excitation.The experimental results show that the whiplash effect of the model is obvious,the damage is mainly concentrated on the top,and the failure mode is consistent with the actual seismic damage characteristics of similar structures.The model reacts differently under different seismic waves.With the increase of seismic excitation amplitude,the natural frequency drops down by 27.4%,and the first order damping ratio is increase 2.55 times compared to that without the experience of earthquakes.The displacement angle of the top storey reaches 1/116,while the structure has already entered into the state of serious damage under the action of an earthquake with 8 degrees of seismic fortification intensity.Protective measures should be taken for similar ancient towers in district of 8 degrees and above 8.
作者
钱春宇
徐敦峰
浩文明
于英文
谢启芳
QIAN Chunyu;XU Dunfeng;HAO Wenming;YU Yingwen;XIE Qifang(Jikan Research Institute of Engineering Investigations and Design,Co.,Ltd.,Xi’an 710043,China;State Key Laboratory of Green Building in Western China,Xi’an University of Architecture&Technology,Xi’an 710055,China;Jinan Zhongjian Architectural Design Institute Co.,Ltd.,Jinan 250101,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2020年第22期67-75,共9页
Journal of Vibration and Shock
基金
国家自然科学基金项目(51878550)
陕西省教育厅重点实验室项目(08JS066)
国机集团科技发展基金项目(13科192号)。
关键词
小雁塔
砖石古塔
振动台试验
动力特性
动力响应
抗震性能
Xiaoyan pagoda
ancient masonry pagoda
shaking table test
dynamic characteristics
dynamic response
seismic performance
