DEVELOPMENT OF REAL-TIME GEOPHYSICAL EXPLORATION SYSTEM BASED ON ARRAY OBSERVATION OF THREE-COMPONENT MICROTREMORS

基于三分量微震阵列观测的实时地球物理勘探系统开发

• 批准号: 08555140
• 负责人: TOKIMATSU Kohji
• 金额: $ 3.01万
• 依托单位: TOKYO INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08555140/
• 关键词: Microtremors; Array observation; Surface waves; Rayleigh waves; Love waves; Shear wave profile; Amplification; F-k spectrum analysis; 地震探査

Field techniques and analytical procedures have been presented for geotechnical site characterization using microtremor three-component ground motions, in addition to their applicability for evaluating spatial variation of soil profiles and ground motion characteristics. The present system can readily provide Rayleigh- and Love-wave dispersion curves as well as H/V spectra from spectrum analyzes of microtremor three-component ground motions. The dispersion curves and H/V spectra of surface waves have been theoretically derived in which the effects of higher-modes can be taken into account. Inverse analyzes using both Rayleigh-wave dispersion curve and Love-wave dispersion curve or H/V spectra have been presented for determining shear wave velocity profiles.It is shown that :(1) The theoretical dispersion curve of Rayleigh waves shows a good agreement with those determined by te F-k spectrum analysis of the microtremor vertical motions in any case.(2) The theoretical dispersion curve of … More Love waves shows a good agreement with those determined by the F-k spectrum analysis of the microtremor transverse horizontal motions, if microtremors propagate from one direction.(3) The proposed H/V spectrum of surface waves shows a good agreement with observed microtremor H/V spectrum, claiming its validity.(4) The proposed inversion process using both Rayleigh-wave dispersion curve and Love-wave dispersion curve or H/V spectra can yield more reliable shear wave velocity profiles than that using Rayleigh-wave dispersion curve only.To demonstrate the effectiveness of the proposed methods, microtremor measurements using arrays are conducted in Kushiro and Kobe and the shear structures in those areas are estimated down to depths of about 50 m and 1.5 km, respectively. The estimated shear structures are in good agreement with those determined by the conventional methods, indicating the effectiveness of the proposed method. Effective stress response analysis is then made using the estimated soil profiles. The computed distribution of the peak ground velocity and acceleration as well as the transfer funcion between stations are consistent with those observed during the earthquakes, suggesting that the proposed methods are promising. Less

现场技术和分析程序已提出的岩土工程场地特性，使用微动三分量地面运动，除了其适用性评估土壤剖面和地面运动特性的空间变化。本系统可以很容易地提供瑞利波和洛夫波频散曲线，以及H/V谱的脉动三分量地震动的频谱分析。从理论上导出了表面波的色散曲线和H/V谱，其中可以考虑高阶模的影响。本文提出了用瑞利波频散曲线和洛夫波频散曲线或H/V谱来反演横波速度剖面的方法，结果表明：（1）在任何情况下，瑞利波理论频散曲线都与脉动垂直运动的F-k谱分析结果吻合得很好。(2)理论色散曲线 ...更多信息 当地脉动从一个方向传播时，Love波与地脉动横向水平运动的F-k谱分析结果吻合较好。(3)所提出的面波H/V谱与观测到的地脉动H/V谱具有较好的一致性，证明了其有效性。(4)本文提出的利用瑞利波频散曲线和Love-wave频散曲线或H/V谱反演横波速度剖面的方法比仅利用瑞利波频散曲线反演横波速度剖面的方法更可靠。在钏路和科比进行了利用台阵的脉动测量，并估计了这些地区的剪切结构，其深度分别为50 m和1.5 m公里，分别。计算结果与传统方法计算结果吻合较好，表明了该方法的有效性。有效的应力响应分析，然后使用估计的土壤剖面。计算得到的地面峰值速度和加速度的分布以及台站间的传递函数与地震时的观测结果基本一致，表明本文方法是可行的。少

项目成果

田村 修次: "3次元多層地盤上の水平点加振源から発生する実体波の距離減衰" 第32回地盤工学研究発表会. 859-860 (1997)

Shuji Tamura：“三维多层地面上水平点激励源产生的体波的距离衰减”第 32 届岩土工程研究会议 859-860（1997 年）。

Arai, H.: "Comparison of Local Amplifications Estimated from Microtremor F-k Spectrum Analysis with Earthquake Records" Proc.,11th World Conf.on Earthquake Engineering. CD-ROM,3. 8 (1996)

Arai, H.：“根据微动 F-k 频谱分析估计的局部放大与地震记录的比较”Proc.，第 11 届世界地震工程大会。

Tokimatsu, K., Arai, H., and Asaka, Y.: "Deep Shear-Wave Structure and Earthquake Ground Motion Characteristics in Sumiyoshi Area, Kobe City, Based on Microtremor Measurements" Jour.of Structural and Construction Engineering, AIJ. No.491. 37-45 (1997)

Tokimatsu, K.、Arai, H. 和 Asaka, Y.：“基于微震测量的神户市住吉地区的深层剪切波结构和地震地震动特征”Jour.of Structural and Construction Engineering，AIJ。

Kohji TOKIMATSU: "Two-dimensional Shear Wave Structure and Motion Characteristics in Kobe Based on Microtremor Measurements" Geotechnical Earthquake Engineering and Soil Dynamics 3rd Conference,August 3-6, Seattle, Washington, GEO-INSTITUTE ASCE 1998. (発表

Kohji TOKIMATSU：“基于微震测量的神户二维剪切波结构和运动特征”岩土地震工程和土壤动力学第三次会议，8 月 3-6 日，华盛顿州西雅图，GEO-INSTITUTE ASCE 1998。（演示文稿）

田村 修次: "3次元多層地盤における地中水平点加振の応答変位にしめる表面波と実体波の割合" 日本建築学会大会学術講演梗概集. 237-238 (1997)

Shuji Tamura：“三维多层地面中水平点激励的响应位移中的表面波和体波之比”日本建筑学会会议学术讲座摘要237-238（1997）。