摘要
为研究地震烈度对地下圆形隧洞频谱特性及空间效应的影响,开展几何相似比为1:30的振动台模型试验。介绍模型试验中的测点布置、输入波型及加载方案,对模型场域及隧洞结构的加速度反应和频谱特性进行研究,对比结构不同观测面处的地震响应差异,分析不同地震动强度、加载波形及空间位置对圆形隧洞结构频谱特性的影响。研究结果表明:模型地基及结构的加速度响应受输入波形及加载强度的影响明显;地震强度越大、埋深越浅,峰值加速度越大,反之则越小,而加速度放大系数随着地震强度的增高而降低;地基与结构频谱特性具有典型的"低扬高抑"特征,同一测点在相同地震波不同强度作用下得到的傅氏谱频谱特性基本一致,卓越频率所在频段基本相同,而傅氏谱值大小与输入地震动强度有关;结构加速度动力响应具有显著的空间效应,且与加载波形、输入地震动强度和观测面的位置有关。
In order to study the influence of different seismic intensity on the frequency spectrum and the spatial effect of the underground circular tunnel,a shaking table model test was carried out with geometric similarity ratio of 1/30.The arrangement of measuring points,the input wave type and the loading scheme in shocking model test are introduced briefly.The acceleration responses and spectrum characteristics of the model foundation and structure as well as the differences of seismic responses at different observation planes are studied.Meanwhile,the effects of different ground motion intensity,loading waveform and spatial position on the spectrum characteristics are analyzed.The results show that the acceleration responses of the model foundation and structure are obviously affected by the input waveform and the load intensity.Although the peak acceleration is proportional to the seismic intensity and inversely proportional to the depth,the acceleration amplification coefficient is inversely proportional to the load intensity.The frequency spectrum has a typical characteristics of“low lift and high suppression”.The Fourier frequency spectrum characteristics of the measured points are the same under different loading conditions and the Fourier amplitude spectrum is related to the intensity of input ground motion.The acceleration responses of the structure have a significant spatial effect,which is affected by the loading waveform,input ground motion intensity and the the observation position.
作者
王建宁
窦远明
李雨润
魏明
朱旭曦
WANG Jianning;DOU Yuanming;LI Yurun;WEI Ming;ZHU Xuxi(School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China;Civil Engineering Technology Research Center of Hebei Province,Tianjin 300401,China;School of Transportation,Nantong University,Nantong 226019,China;College of Architecture and Civil Engineering,Beijing University of Technology,Beijing 100124,China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2018年第11期2909-2919,共11页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(61503201
51008110)
河北省自然科学基金资助项目(E.2013202118)
河北省研究生创新资助项目(CXZZBS2017033
CXZZBS2018038)
关键词
地下隧洞
振动台试验
地震烈度
频谱特性
空间效应
underground tunnel
shaking table test
seismic intensity
frequency characteristic
spatial effect
