Analysis of the Effect of U-Turns Geometry on the Accident Rate  (Case Study: Sanandaj)

Hasaninasab, Seyed Shahab; Rahimi, R

Analysis of the Effect of U-Turns Geometry on the Accident Rate (Case Study: Sanandaj)

Document Type : Original Article

Authors

Seyed Shahab Hasaninasab ¹
r rahimi ²

¹ Civil engineering department, engineering faculty, Razi university, Kermanshah, Iran

² Hamedan National Iranian Gas Company, Hamedan, Iran.

Abstract

The use of U-turns as one of the methods for access management and psycho-facilitation of movement has been widely developed in Iran since the end of the year 82, in which the signalized intersections were converted to U-turn. Uprights made in Sanandaj are mainly located on highway roads in the city of Durran. The goal of the project was to reduce the delay and increase the driver's mental capacity. This thesis examines the effect of these U-turners on traffic safety. In this research, powerful statistical methods have been used for safety analysis, in which 10 signaled intersections in Sanandaj, which have been converted to U.S., have been studied. The results of this study on the geometry of the U-turns show that an average of 10 percent increase in the width of the U-turns produced a 2.2 percent reduction in fatal accidents, 4.7 percent accidents, 4.81 percent accidents and 5.18 percent of accidents Decreases. Also, an increase of 10% from the intersection causes a decrease of 0.6% in the number of fatal accidents, 2.7% in accidents, 1.81% in accidents and 2.5% in accidents. Also, an increase of 10% in average daily traffic caused a 1.62% increase in fatal accidents, 1. 54% accidents, 1.95% accidents and 2.5% accidents. Finally, the average speed of the main path parameter was also examined and the results showed that a 10% increase in speed caused a slight and near zero increase in the number of accidents, which is statistically insignificant.

Keywords

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