Preliminary Study Of Earthquake Early Warning Technology Of High Speed Railway

Earthquake early warning technology is developing rapidly in recentyears.By initial information of near source seismic stations, it estimate focalshock parameters and predict the earthquake effect of the target zonebeforedestructive waves reach the region.Earthquake early warning system hasbeen put into use in some countries and regions, it not only provides servicefor the general public, and provides security for critical infrastructure.In thispaper, under the background of the rapid development of high-speed railwayconstruction in our country, based on Fujian digital seismic network platform,service in the high-speed of Fuzhou-Xiamen, the main researchincludes:earthquake location through single station, instrument intensityprediction technology, the intensity distribution along the railway, warningtimeand blind areaestimatingfor P wave, S wave and Peak GroundAcceleration (short for PGA).According to the content of our study, wepreliminarily set up a framework for the earthquake early warning system forhigh-speed railway. Main research work is as follows:1.In this paper, in reference to foreign high-speed railway earthquakewarning system of the locating methods, on the basis of the actual situationof Fujian regional seismic network construction, we locate earthquake byVoronoi diagram (hereinafter referred to as V) in the high-speed railwayearthquake early warning system in our country, assuming that the locationoffirst triggeredstation is the epicenter.In eachV diagram of polygon area, wediscrete grid andassumes that each grid point is one source, and then wecarryon the statistics about the location error in each V diagram. Based on thelocation error, we assess the intensity prediction along the railway.Throughthe analysis of the evaluation results, based onSeismic network in Fujianregion, locationaccuracy by single station through V diagram can meet therequirements of high speed railway earthquake early-warning location.2.Based on acceleration data from kik-net,firstly,weproposed severalgroups of real-time intensity forecasting formula according to theinstruments intensity calculation formula, then we verify the predictionformula throughWenchuan, Chi-Chi earthquake, and at last the factorsaffecting the prediction effects are simply analyzed. Through the comparisonof test results, we recommend practical intensity prediction formula.3.High-speed rail is linear distribution. Different sections of the railwaysuffer different levels of earthquake disasters in an earthquake. This paperargues that forecasting intensityof the first trigger station is the epicenterintensity.Using the intensity attenuation relationship, we can draw intensitycontour map and deduce the seismic intensity calculation formula along therailway According to the relative position between first trigged station andrailway, combined with the intensity contour map and the intensity attenuation relationship, earthquake effect along the railway can be quicklyevaluated.4.Warning time and blind area estimation relate to many factors inearthquake early warning system for high-speed railway.This article ignorethe information transmission delay and early warning information releasingtime, etc. We focus on thetime consuming of seismic intensity prediction forthe first trigged station.Combining intensity prediction formula and seismicnetwork distribution in Fujian region, the author argues that early warninginformation can be released in3seconds after the first station beingtrigged.By this way, wecan guarantee certain intensity prediction accuracy,and meet the timeliness requirements forhigh-speed railway.With the aid ofvelocity structure model of southern China, in Fujian province we alsousethe grid discretization method, investigating P wave, S wave, and PGAwarning time.Finally, with the help of potential seismic source in southeastof China,the warning time and intensity of four important railway stationsuch as Fuzhou, Xiamen can be assessed.