Research On The Value Rule Of Influencing Factors Of Highway Traffic OD Estimation Based On Orthogonal Experiment

Traffic demand analysis is the basic work of road traffic planning and traffic organization program analysis,and OD is the most basic basis.OD estimation is a method to obtain OD matrix.When it is difficult or costly to directly obtain OD matrix and it is more convenient to obtain road section flow,it becomes very necessary to carry out OD estimation through road section flow.However,the use of Trans CAD software for OD estimation,as a result of the actual road traffic in the network there are many influence factors in OD estimation,reasonable variable value is relatively difficult,so lead to OD estimation results tend to have large discrepancy with actual condition.Therefore,aiming at the existing problem of application of OD estimation,based on the orthogonal test design scheme for OD estimation,through analyzing the test results,summarized to improve highway network by some regularity of OD estimation accuracy.Firstly,the paper introduces the theory of OD estimation.Secondly,the influencing factors of OD estimation accuracy are summarized.The related theory of orthogonal test design is introduced again,and the range of influence factors is studied to provide parameter selection for orthogonal test design.Finally,based on the orthogonal test,the OD estimation of Shijiazhuang municipal road network is carried out and the test results are analyzed.The same method is used to carry out the OD estimation of Xingtai municipal road network and Handan municipal road network and the test results are analyzed.The results show that,it can be seen that the precision of the stochastic user equilibrium allocation method is better,and it is suggested to use the stochastic user equilibrium allocation method to carry out OD estimation.Increase the number of test sample sections of road traffic network of the proportion of the total error is smaller than the sample section average relative error is bigger,the proportion of the overall enhances the precision of OD estimation,but the extent of change is not very big,so the precision allowed under the premise of suggested to select 10% sample sections for OD estimation,can have better precision OD matrix can also reduce the workload of data acquisition;In the sample section,try to select more sections with the maximum flow,so that the precision of OD estimation can be higher.The suggested values of parameters ? and ? are given.The conclusion of the above laws enriches the content of OD estimation and has important reference significance for traffic demand analysis.