基于偏置伽马分布的高速铁路地震预警及紧急处置时延特性分析

通过对高速铁路地震预警及紧急处置时延特性进行分析,提出1种地震预警及紧急处置时延精确概率分布函数——偏置伽马分布模型。采用国内和日本天然地震记录数据作为输入对某高速铁路地震预警系统进行现场试验,利用试验数据验证了偏置伽马分布概率密度函数描述时延的偏置量及分布特征的有效性,表明地震预警时延和紧急处置时延服从偏置伽马分布。通过建立不同紧急处置路径和不同预警级别情况下时延的概率事件模型,采用偏置伽马分布模型分析高速铁路各级别地震预警与紧急处置总时延分布特征与规律,并进行综合比较与评价。结果表明:在Ⅱ级和Ⅲ级地震预警情况下,从首台站地震P波初至,到铁路局中心系统以GPRS方式向车载装置发送地震紧急处置信息,再到车载装置自动触发列车紧急制动,总时延在50%,70%和95%概率下分别为2.34,2.68和3.63s,证明我国高速铁路地震预警及紧急处置技术方案有效、可行。

Analysis of Time Delay Characteristics of Earthquake Early Warning and Emergency Disposal for High Speed Railway Based on Offset Gamma Distribution

By analyzing the time delay characteristics of earthquake early warning and emergency disposal for high speed railway,a kind of accurate probability distribution function for the time delay of earthquake early warning and emergency disposal,namely,offset gamma distribution model,was put forward.A field test of high speed railway earthquake warning system was carried out with the domestic and Japanese earthquake records as inputs.The effectiveness of the offset gamma distribution probability density function to describe the offset and distribution characteristics of the time delay was verified using test data,and it showed that the time delays of earthquake early warning and emergency disposal obeyed the offset gamma distribution.By means of modeling the probability events of time delays under different emergency disposal paths and different warning levels,the offset gamma distribution model was adopted to analyze the characteristics and regularities of the total time delay distributions of earthquake early warning and emergency disposal at all levels of high speed railway,and the comprehensive comparison and evaluation were also made.Results show that,at levels II and III,the total delay from the time of the first arrival of P wave at the single station to the time of railway administration center system sending emergency disposal information to the onboard device by means of GPRS and then to the time of the onboard device automatically triggering train emergency braking is 2.34,2.68 and 3.63 s under the probabilities of 50%,70% and 95% respectively.It is proved that the technical scheme of earthquake early warning and emergency disposal for high speed railway in China is effective and feasible.