基于福建区域地震台网的高速铁路预警能力评估及烈度预测方法探讨

发布时间：2018-03-16 18:07

本文选题：高速铁路地震预警　切入点：V图定位　出处：《中国地震局工程力学研究所》2013年硕士论文　论文类型：学位论文

【摘要】：地震预警技术近年来发展迅速，它主要利用震源附近地震台站记录到的地震动初始信息，，快速估计相关参数并预测预警目标区的地震影响，在破坏性地震波到达该区域前向其发布地震预警信息。地震预警系统已经在一些国家和地区投入使用，它不仅为普通公众提供服务，而且为重要的基础设施提供安全保障。本文在我国高速铁路建设飞速发展的背景下，以福建数字地震台网为基础平台，服务于福厦高铁，主要研究包括：单台V图预警定位方法，仪器烈度预测技术，铁路沿线烈度分布估计，以及P波、S波、PGA预警时间及盲区的评估，本文根据所研究的内容初步搭建了高速铁路地震预警系统的框架。主要研究工作如下： 1．本文在参考国外高速铁路地震预警系统中地震定位方法的基础上，结合我国福建地区地震台网建设的实际情况，在我国的高铁预警系统建设中采用Voronoi(以下简称V图)剖分定位的方法，假定首个触发台站的位置即为震中。在台站控制的V图多边形区域内进行网格离散化，假设每个网格点即为一个子震源，统计了单台定位时，每个台站利用V图剖分技术造成的定位误差，并藉此评估定位误差对铁路沿线烈度预测产生的影响。通过对评估结果的分析，发现对于福建地区的地震观测台网，单台V图定位的精度基本能够满足高速铁路地震预警定位的要求。 2．收集了日本KiK-net部分加速度资料，在现有仪器烈度计算公式的基础上，提出了几组实时预测烈度的公式，随后利用汶川、集集地震对预测公式进行检验，并对影响预测效果的因素进行了简单的分析。通过对检验结果的对比，推荐了实用性较强的烈度预测公式。 3．高速铁路为线状分布，一次地震中不同区段遭受的地震影响不尽相同。本文认为首个触发台站的预测烈度即为震中烈度，利用烈度衰减关系，绘制了烈度衰减等值线图并推导了铁路沿线不同区段遭受地震烈度的计算公式。首个台站触发时，根据其与铁路的相对位置，结合烈度衰减等值线图和衰减关系，铁路沿线遭受的地震影响可以快速估计。 4．高速铁路单台预警时间与盲区的估计与众多因素有关，本文忽略信息传输延迟、预警信息发布耗时等，着重考虑了单台预警时仪器烈度预测需时。结合仪器烈度预测公式和福建地区台网的分布及密度，本文认为首台触发后3秒发布预警信息即能保证一定的烈度预测精度，又兼顾了铁路预警时效性的要求。以此为基础，采用华南速度结构模型，在福建省区域内同样采用网格离散化方法，统计分析了铁路P波、S波、PGA的预警时间及盲区分布。最后，利用东南区域潜在震源资料，对福厦高铁沿线福州、厦门等四个重要站点具有的预警时间和可能遭受的烈度进行评估。
[Abstract]:Seismic early warning technology has developed rapidly in recent years. It mainly uses the initial information of ground motion recorded by seismic stations near the source to estimate the relevant parameters quickly and to predict the earthquake effect in the target area of early warning. Issue early warning information to destructive seismic waves before they reach the region. Earthquake warning systems are already in use in some countries and regions, not only for the general public, but also for the general public. In the context of the rapid development of high-speed railway construction in China, this paper takes the Fujian Digital Seismic Network as the basic platform to serve the Fuzhou-Xiamen high-speed railway. The main research includes: single V map early warning positioning method, instrument intensity prediction technology, intensity distribution estimation along the railway line, and PGA early warning time and blind area assessment of P wave and S wave. In this paper, the frame of earthquake early warning system of high-speed railway is built up according to the contents of the research. The main research work is as follows:. 1. On the basis of referring to the seismic location methods in the earthquake early warning system of foreign high-speed railway, this paper combines the actual situation of seismic network construction in Fujian area of our country. In the early warning system construction of high-speed railway in China, Voronoi (hereinafter referred to as V chart) is used to divide and locate, and the position of the first trigger station is assumed to be the epicenter. The grid is discretized in the polygon region of the V diagram controlled by the station. Assuming that each grid point is a sub-seismic source, the positioning errors caused by the V-map subdivision technique are calculated for each station when a single station is located. Through the analysis of the evaluation results, it is found that the earthquake observation network in Fujian area, The accuracy of single V map location can meet the requirements of earthquake early warning location of high speed railway. 2. The partial acceleration data of KiK-net in Japan are collected. Based on the existing formulas for calculating the intensity of the instrument, several real time intensity prediction formulas are put forward, and then the prediction formulas are tested by Wenchuan and Jiji earthquakes. Based on the comparison of the test results, the practical intensity prediction formula is recommended. 3. The high-speed railway is a linear distribution, and different sections of an earthquake are affected by different earthquakes. In this paper, it is considered that the predicted intensity of the first triggering station is epicentral intensity, and the intensity attenuation relation is used. The intensity attenuation isoline diagram is drawn and the formula for calculating the seismic intensity of different sections along the railway line is derived. When the first station triggers, according to its relative position with the railway, combined with the intensity attenuation isoline diagram and attenuation relation, The earthquake effect along the railway line can be estimated quickly. 4. The time of single station early warning and the estimation of blind area of high speed railway are related to many factors, such as the delay of information transmission, the time consuming of issuing early warning information, etc. This paper emphatically considers the time required for the prediction of the intensity of the instrument in the case of a single early warning. Combined with the formula of predicting the intensity of the instrument and the distribution and density of the network in Fujian area, this paper holds that the early warning information released at 3 seconds after the first trigger can guarantee certain precision of intensity prediction. On the basis of this, the speed structure model of South China and the method of grid discretization in Fujian province are adopted to analyze the early warning time and blind area distribution of railway P wave S wave and PGA. Based on the potential source data of southeast region, the warning time and potential intensity of four important stations, Fuzhou and Xiamen, along the Fuzhou-Xiamen high-speed railway line are evaluated.
【学位授予单位】：中国地震局工程力学研究所
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P315.9;U298

【参考文献】