公路桥梁随机车流的平稳性和各态历经性检验

Examination of Stationary and Ergodicity of Stochastic Traffic Flow on Highway Bridge

根据6条公路桥梁28条车道上的WIM系统实测车辆信息,分别生成了各车道上的随机车流类型过程。用随机过程理论分别计算得到各随机车流类型过程的集合均值、集合相关函数、时间均值、时间相关函数等随机特性参数。进一步对比分析,验证了所建立的随机车流类型过程的平稳性和各态历经性。结果表明:从实际公路上调查一定数量的车辆,其统计特性能够代表总体样本的车流信息,对车辆各种特征的统计结果具有代表性,可为公路桥梁随机车辆荷载模型的建立提供参考。

According to the information of vehicles collected by WIMs in-situ on 28 lanes of 6 highway bridges, stochastic processes of the type of traffic flow on each lane are generated respectively. On the basis of the theory of stochastic process, the random characteristic parameters such as ensemble means, aggregate correlation functions, time means and time correlation functions of stochastic traffic flow type processes are calculated accordingly. By further comparison and analysis, the stationarity and ergodicity of the generated stochastic processes of the of traffic flow type are verified. The result shows that when the data of vehicle samples collected by WIMs on actual highways is plenitudinous enough, the statistic characterization is able to represent the total one. The collected statistic characters of vehicles will be the characters of entirety of specimens, which can be a reference for modelling the random vehicle loads on highway bridge.