Investigation of Strong Ground Motion around MTL in Mikawa Area

三河地区MTL周边强地震动调查

• 批准号: 06402044
• 负责人: KURIBAYASHI Eiichi
• 金额: $ 9.15万
• 依托单位: TOYOHASHI UNIVERSITY OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06402044/
• 关键词: M.T.Line; outer zone; inner zone; seismograph; array observation; deep fault; Paraeozoic Era; Fault model

The TASSEM,Toyohashi University of Technology Array System for Strong Earthquake Motions, has been developed around Toyohashi city to observe the strong ground motions of this area and investigate the effects of geological and topographical conditions including fault existence. The earthquake observations and their numerical analysis were conducted as remarked as below.a) The strong motion seismograph has been set up in Shinshiro city (called site 2 in outer zone) and Gamagori city (called site 3 in inner zone) in 1995, in addition to old observation points (called site 1 around TUT) established in 1989. All these observation location are distributed around the Median Tectonic Line (MTL) and installed on the basement in engineering meaning. In total, five earthquake records were observed, four of which occurred in outer zone and one in inner.b) Based on the analysis of such recorded acceleration, unsteady properties of wave propagation due to the scattering within MTL are obvious, that … More are involved with the ratation of principal propagating direction and the occurrence of additional surface wave and different frequency distribution within inner zone and outer zone.c) On the amplification and attenuation of ground motions, even though some records showed trend to amplify the high frequency components when the seismic wave propagated over the MTL,it is difficult to assert such results only from MTL effect, because we need to separate the local site effect of topographical conditions besidea near field soil condition. On the other hand, the amplification in seaside area were always observed both in inner zone and outer zone, which is considered due to the effects of thick alluvium.d) The coherency functions of different observation sites showed various value with respect to different focal region. It is considered that both MTL and site effects on ground motions behaved associated with seismic wave propagating routes.e)The theoretical analysis on ground motion indicated that the amplification due to local site conditions was significant, but the Q value in both side of MTL,as an index of attenuation of wave propagation, showed no much difference. More accurate simulations have to be experimented to imterpret the MTL effects. Less

在丰桥市周围开发了用于强震运动的TASSEM，即丰桥工业大学阵列系统，以观测该地区的强地面运动，并调查地质和地形条件的影响，包括断层的存在。地震观测和数值分析如下：a)1995年在新四郎(外区称为2号站)和伽马库里市(内区称为3号站)建立了强震地震仪，另外还有1989年建立的老观测点(图坦卡蒙周围的1号站)。所有这些观测点都分布在中值构造线(MTL)周围，并安装在具有工程意义的基底上。共观测到5次地震记录，其中4次发生在外区，1次发生在内层。b)根据记录的加速度分析，MTL内部散射引起的波传播的非定常特性是明显的，…C)对地面运动的放大和衰减，尽管有些记录显示地震波在MTL上传播时有放大高频分量的趋势，但仅由MTL效应很难断定这种结果，因为我们需要在近场土壤条件之外分离地形条件的局部场地效应。另一方面，海岸区的放大效应通常出现在内带和外带，这是由于厚积层的影响。d)不同观测点的相干函数在不同的震源区表现出不同的值。认为MTL和场地对地面运动的影响都与地震波的传播路径有关。e)对地面运动的理论分析表明，局部场地条件对地面运动的放大作用是显著的，但作为波传播衰减指标的MTL两侧的Q值没有太大差异。必须进行更精确的模拟来解释MTL效应。较少

项目成果

Kawara, K.: "Earthquake motion Observation and analysis in Mikawa area with emphases on MTL effect (Part II)" Procs.of the 52th annual conf.of The JSCE. Vol.I-B. 572-573 (1997)

Kawara, K.：“以 MTL 效应为重点的三河地区地震运动观测与分析（第二部分）” JSCE 第 52 届年度会议记录。

桶谷 秀人: "三河地域における地震動の地盤増幅特性" 平成9年度土木学会中部支部発表会. (1998)

Hideto Oketani：“三河地区地震运动的地面放大特性”1997年日本土木工程师学会中部分会演讲（1998）。

Eiichi Kuribayashi: "A comparative study on typical measures of earthquake preparedness in local governments between Japan and U. S. A." Proc. of 6th International Conf. Soil Dynamics & Earthquake Engineering(The Kobe Earthquake). 111-145 (1995)

Eiichi Kuribayashi：“日本和美国地方政府典型防震措施的比较研究”

松井欣嗣: "1995年兵庫県南部地震におけるライフラインの復旧率について" 第50回土木学会学術講演集. 1-B. 1184-1185 (1995)

Kinji Matsui：“关于 1995 年兵库县南部地震期间生命线的恢复率”第 50 届日本土木工程师学会学术会议论文集 1-B 1184-1185（1995 年）。

松井欣嗣: "兵庫県南部地震による震災波及構造について" 第51回土木学会学術講演集. 1-B. 708-709 (1996)

松井欣二：《关于兵库县南部地震引起的地震灾害涟漪结构》第51届日本土木工程学会学术会议论文集1-B 708-709（1996年）。