Seismic P-Wave Phase Identification Method for High-speed Railway Earthquake Early Warning System Based on Fractal Dimension
The implementation of high-speed railway earthquake early warning system can better guarantee the operation safety of high-speed railway.As small earthquakes with magnitude below 5 account for more than 95%of seismic events,improving the recognition speed and accuracy of high-speed railway early warning system in identifying small earthquake phases can effectively guarantee the safe operation of high-speed railways.In this paper,a P wave recognition algorithm based on fractal dimension was proposed to optimize the traditional calculation method of fractal dimension and improve the calculation speed of fractal dimension.The fractal slope curve was introduced and divided into four stages to analyze the fractal slope characteristics of critical points.The precise arrival time of seismic waves was determined by detecting the extreme moment of fractal slope.The proposed algorithm has an average error of 0.006 3 s and standard deviation of 0.043 8 s,which fully meets the requirements of timeliness and accuracy of earthquake warning system for high-speed railway.
high-speed railwayearthquake early warningP wave identificationshort time average/long time averageAkaike information criterion