地震研究

基于合作市区41处地脉动观测点数据的快速傅里叶变换和单点H/V频谱分析结果,总结了合作市区场地条件的地脉动特征,并结合钻孔揭示的场地条件资料,反演合作市区的覆盖层厚度。根据合作地区不同局部地形观测数据和数据分析结果,分析了地形对地脉动的放大效应。结果表明:合作市区场地的卓越周期主要分布在0.1～0.2 s,与合作市区场地条件相符; 2条剖面H/V频谱分布稳定,覆盖层厚度地脉动反演结果与钻孔揭示厚度吻合较好。

First,based on frequency spectral analysis result of microtremor observation data of 41 observation points in Hezuo City by fast Fourier transform(FFT)and horizontal-to-vertical spectral ratio of single point(H/V),we summarized the ground microtremor characteristic in site condition of Hezuo City. Second,combining the site condition of drill exploration,we inversed the overburden thickness of the Hezuo City. Finally,we analyzed the amplification effect of topography on microtremor combining with the topography observation data in different local area of Hezuo City and its data analysis result. The results show that the predominant period of sites mainly distributes between 0.1 s and 0.2 s,which is suitable with site condition in Hezuo. The distribution of H/V frequency spectrum of two profiles is stable and the overburden thickness inversed by microtremor are very close to the real thickness acquired by borehole.

引言
1 地脉动现场观测
2 数据处理
3 合作市区地脉动特征
4 地脉动在覆盖层探测中的应用
5 结论

图1 卓越周期统计<br/>Fig.1 Predominant periods statistic of different sites

图1 卓越周期统计
Fig.1 Predominant periods statistic of different sites

图2 地脉动原始波形数据<br/>Fig.2 Microtremor original waves

图2 地脉动原始波形数据
Fig.2 Microtremor original waves

图3 地脉动数据FFT分析结果<br/>Fig.3 Analysis results of microtremor wave in FFT frequency spectrum processing

图3 地脉动数据FFT分析结果
Fig.3 Analysis results of microtremor wave in FFT frequency spectrum processing

图4 单个测点H/V频谱分析<br/>Fig.4 Analysis results of H/V frequency spectrum

图4 单个测点H/V频谱分析
Fig.4 Analysis results of H/V frequency spectrum

图5 两条主干路剖面的H/V频谱分布(a)铜钦街剖面;(b)念钦街剖面
Fig.5 H/V spectrum distribution of two main streets profile(a)the profile of Tongqin Street;(b)the profile of Nianqin Street

表1 合作市区场地条件<br/>Tab.1 Testing site conditions in Hezuo City

表1 合作市区场地条件
Tab.1 Testing site conditions in Hezuo City

图6 反演合作覆盖层厚度分布<br/>Fig.6 Distribution of overburden thickness in Hezuo City

图6 反演合作覆盖层厚度分布
Fig.6 Distribution of overburden thickness in Hezuo City

图7 覆盖层厚度剖面
(a)铜钦街剖面;(b)念钦街剖面
Fig.7 Profile of overburden thickness of two main streets

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备注

引言

1 地脉动现场观测

2 数据处理

3 合作市区地脉动特征

4 地脉动在覆盖层探测中的应用

5 结论

期刊信息