Abstract: It has lots of shortage that takes design speed as highway alignment design criteria，and operating speed is closed related witI1 traffic safety．At the same time，highway alignment design is an inter national universal method of highway alignment designinthe current，which has been recognized and valued gradually in china，but related researchis stilltheless．According to the measured data of TAI-JIU freeway operating speed,the papertakes use of Matlab Artificial Neural NetWork to establish the Neural NetWork modal ofthe relationship between operating speed and horizontal aligment elements，use which to make highway alignment design and evaluate the operating speed，and the high forcast precision has been found．So it has the factual value in use．

Key words: Matlab, BP neural network, design speed, operating sputa

摘要： 基于太旧高速公路运行车速实测数据，利用Madab人工神经网络建立运行车速与平面线形要素之问的神经 网络关系模型，以期用于对新建公路的线形设计和已有公路的运行车速评估．在太旧高速公路应用发现预测精度 较高。有实际利用价值．

关键词: Matlab, BP人工神经网络, 设计车速, 运行车速