Strong motion and damage prediction for huge subduction-zone earthquakes based on a high precision prediction technique

为了建立大俯冲带地震定量震害预测技术并验证其有效性，本研究进行了以下三个方面的研究：1)震源过程分析与强震预测技术的发展；2)震源特征提取与地下结构施工；3)震害定量预测模型的建立。对于第一个任务。1、确定了Off-Tokachi和Off-Kushiro地区7次板间地震的强震发生区。在此基础上，利用经验格林函数法对下一次托南开地震的强运动进行了评价，并对该方法的有效性进行了讨论。在统计方法上，将频谱分离技术和时变特征建模技术应用于K-NET等国家网络获取的10秒宽带周期范围内的强运动数据。我们用它们来做一个大的…更多的俯冲带地震。对于第一个任务。2 .利用收集到的地理特征分类信息，建立了千叶市表层土壤结构三维模型，并对模型的有效性进行了验证。针对诺比平原强运动的基本特征，对观测到的强运动记录进行了多种分析。为了更精确地确定地下结构，提出了一种改进的接收函数法。对于第一个任务。提出了基于微震或余震记录的结构响应特征构建结构模型的方法，并与以往经验进行了对比验证。最后利用强震预测技术和结构损伤预测技术对南开地震进行了强震和震害预测。因此，虽然震源地区达到7级地震烈度的强烈运动将造成严重的破坏，但在人口集中地区的预测破坏似乎没有我们所担心的那么大。少

In this research, in order to develop a quantitative damage prediction technique for a great subduction-zone earthquake and to verify its validity, the following three investigations were performed :1)Analysis of a source process and the development of the strong motion prediction technique,2)Extraction of site characteristics and the construction of underground structures, and3)Model creation for quantitative damage prediction.For task no.1, the strong motion generation areas were determined for seven interplate earthquakes in Off-Tokachi and Off-Kushiro regions. Then the empirical Green's function method was used to evaluate strong motions during the next Tonankai earthquake and the validity of the method was discussed. For statistical approach, the spectrum separation technique and the time-variation characteristic modeling technique are applied to strong motion data obtained by national networks such as K-NET for a broadband period range up to 10 seconds. We used them for a large s … More ubduction-zone earthquake.For task no.2 by using collected information on geographical feature classification for Chiba City three-dimensional surface soil structure model was built, and the validity of the model was shown. As for the fundamental characteristics of strong motions in Nobi Plain, various analyses were performed on observed strong motion records. For more precise determination of an underground structure, an improved receiver function method was proposed.For task no.3 the technique how to construct a structure model based on its response characteristics obtained from microtremor or aftershock records was proposed, and its verification was carried out by comparing it with past experience. Finally strong motion and damage prediction was performed for the Nankai earthquake by using prediction technique for strong motions and for structural damage. As a result, although heavy damage will be generated by strong motions reaching seismic intensity of 7 in the source region, the predicted damage in the population concentrated areas does not seem so large as we had been afraid of. Less