摘要
周期性材料存在某些固定的频率带,该频率带对弹性波具有选择性透过的作用,处于频率带范围内的弹性波不能透过周期性材料,可以为工程结构减隔震、减振、降噪、消波和隔热等的设计与开发提供新途径。为验证周期性材料的衰减域特性以及对地震波的阻隔作用,减小地震作用下工程结构的动态响应,基于Bloch-Floquet理论,从理论上推导出周期性材料的频散关系,给出周期性材料的频率带隙。建立一维层状周期性基础和钢筋混凝土基础反应堆厂房数值模型和缩尺模型,分别以正弦波扫频和地震波输入的方式,通过振动台试验对周期性基础和钢筋混凝土基础的反应堆厂房进行动态响应分析和滤波效果分析。结果表明,一维周期性基础存在频率带隙,处于该频率段内的地震波无法穿过周期性基础,隔震效果约为90%,且不会增大结构的相对位移;而钢筋混凝土基础则放大结构的动力响应。因此,通过调节周期性基础频率带隙宽度使其覆盖地震波的主要频段能够有效地阻隔地震波的传播,极大地减小工程结构的动力响应,可以用于工程结构基础隔震和减振。
There are certain frequency band gaps in periodic materials.The frequency band gap has a selective transmission effect on elastic waves,which cannot pass through the periodic materials when the main frequency is filled in the frequency band gaps.Thus,it can provide new methods for seismic isolation,vibration isolation noise reduction,wave elimination and thermal insulation design and development in engineering structures.Based on Bloch-Floquet theory,the dispersion relationship of periodic materials was theoretically derived,and the frequency band gap of periodic materials was provided.The reactor building numerical model and scaled model with one-dimensional layered periodic foundation and reinforced concrete foundation were established,and the dynamic responses and filtering effects of periodic foundation and reinforced concrete foundation reactor building were investigated through the shaking table test by means of sine wave sweep frequency and seismic wave input,respectively.The results show that there is a frequency band gap in the one-dimensional periodic foundation,which can block the seismic waves pass through the foundation when the main frequency filled in the range of the frequency band gap.The periodic foundation can provide about 90%isolation effect and does not increase the relative displacement of the structure.On the contrary,the reinforced concrete foundation amplifies the dynamic response of the structure without any reduction.Therefore,the periodic foundation can be used for base isolation and vibration reduction of engineering structures by adjusting the width of the frequency band gap covering the main frequency band of seismic waves.
作者
赵春风
曾超
WITARTO W
MO Y L
ZHAO Chunfeng;ZENG Chao;WITARTO W;MO Y L(School of Civil Engineering,Hefei University of Technology,Hefei 230009,China;Anhui Key Laboratory of Civil Engineering Structures and Materials,Hefei University of Technology,Hefei 230009,China;Department of Civil and Environmental Engineering,University of Houston,Houston 77031,America)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2020年第S02期77-85,共9页
Journal of Building Structures
基金
国家自然科学基金项目(51508148)
关键词
一维周期性基础
基础隔震
衰减域
振动台试验
动力性能
one-dimensional periodic foundation
base isolation
attenuation zone
shaking table test
dynamic response
