Modelling the effect of the urban highway geometric standards to highway capacity

There are more many variables affecting highway capacity. While the effects of these variables could be individual, they sometimes come together. The aim of this study is to investigate the variables affecting highway capacity and to get a model in which the effects of the variables such as the lane width, lengthwise declivity and the number of the vehicles parked along the road can be evaluated.Because there are many uncertainties affecting the highway capacity fuzzy logic method was used in the construction of the model. The model was formed with the help of MATLAB programme.The model was formed for two different urban highway types as one way and ascent pitched, B (Main Street, no stopping zone and less coequal intersection) and C (street, no waiting and parking zone, the capacity of the crossroad is good). Lane width, longitudinal slope and the number of the vehicles parked along the road were considered as input and the practical capacity was seen as output and Mamdani inference method was used in the model.When the results taken from the model for the B and C road types was compared to the data of TS12008 R-Square distribution as 0.9521for B type road and 0.936 for C type road.With the model three variables affecting the highway capacity were evaluated. It is possible to improve the model by increasing the number of variable.Key Words: Fuzzy Logic, Highway Capacity, Highway Geometric Standards