Highway traffic modelling for gdh region3

General Directorate of Highways (GDH) uses Automatic vehicle counting system (AVCS) and Vehicle Classification, or named as Metrocount (MC) extensively. Generelly these measurements or traffic counts on predefined Highway Sections (HS) are made and recorded in four season, 7x24 hour.Clustering highway sections as groups having reliability at least 85% makes possible to analyse and estimate vehicular traffic. Traffic data are generally collected seasonal and seven day 24 hour traffic measures on highway sections by General Directorate of Highways (GDH). The district-wide consolidation and evaluation of all these traffic measurements are needed because traffic data belonging to different months and weeks of seasons are not sufficient for detailed analyses. Available vehicular traffic data recorded on the highway sections are used to cluster highway sections and each group is defined according to their common traffic characteristics and relationships between annual and seasonal variations. By means of these classes generated, first, seasonal impacts or influences on Annual Average Daily Traffic (AADT) are defined or estimated. Second, AADT can be corrected or adjusted. Third, missing seasonal traffics can reliably be estimated. Later if possible, monthly and weekly variations of vehicular traffic flow on the network may be studied for each group by all the data of that group member-highway sections. In other words, the more realistic estimates or arrangements for detailed time periods and their impacts on each other can be made with the help of data pertained to 4 seasons and 12 months changes for different years; together with the characteristics of each group and their members.For this purpose, first; grouping the highway sections according to similarity and reliability levels on the basis of existing data. Then highway sections in the same group can be examinated as a whole of characteristic group. Addition to statistics of similarity and reliability, geographic location and geometric properties and type of the highway sections or segments contributing groups, makes possible to check, be sure or re-evaluate the groups or highway sections on the network.As a result, the necessary predictions or measurements to be provided more reliable data and to increase reliability in analysis or estimates are recommended with suggestions for planning and programming traffic measurements. As a case study sixty eight highway sections generating a network are chosen and their data recorded by AVCS in-between the years 2003-2008, are used to apply procedure and analyses explained.Key Words : Transportation Engineering, Traffic Characterization, Clustering, Discriminant, Analysis, Yearly, Seasonal, Seasonal Expensions