窗函数对地基阻尼比测试的影响  

Influences of window function on subsoil damping ratio

作　　者：侯兴民[1] 孔令召[1] 陈建立[1] 

机构地区：[1]烟台大学,山东烟台264005

出　　处：《地震工程与工程振动》2009年第3期167-172,共6页Earthquake Engineering and Engineering Dynamics

基　　金：教育部科学技术研究重点项目(207062);山东省自然基金项目(Y2008B31);地震工程与工程振动开放实验室资助项目(2007B01)

摘　　要：根据某块体基础的实测数据,讨论了常见平滑方法对时域对数衰减法和频域点峰法竖向阻尼比测试的影响。结果表明,无论采用时域方法还是频域方法,分别对测试曲线进行相邻三点的滑动平均、汉宁窗、哈明窗平滑,阻尼比计算数值差别很小。平滑次数对时域阻尼比结果有影响,平滑次数越多,时域阻尼比有减少的趋势,而频域阻尼比有增大的趋势。滑动平均方法和平滑次数的合理选取,应通过理论和试验方法的研究进一步确定。Effect of window function selection on the subsoil damping ratio of a massive concrete foundation is presented in this paper by using logarithmic decrement method in the time domain and point-peak method in the frequency domain. Minor damping ratio difference among smoothing curves of adjacent three point averaging, Hanning window and Hamming window are found both in the time domain and frequency domain. Influences of number of smoothing times on the subsoil damping ratio is also discussed. It shows that damping ratio decreases as the smoothing times increases in the time domain, and on the contrary in the frequency domain. Selection of window function and number of smoothing times should be studied furthermore on the basis of the real damping ratio value both theoretically and experimentally.

关 键 词：时域 频域 地基阻尼比 窗函数 

分 类 号：P315.98[天文地球—地震学] TU476.1[天文地球—固体地球物理学]