الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
One of the shortcomings of the design speed concept is that it uses the design speed of the most restrictive geometric element as the design speed of the entire road. This may lead to potential inconsistencies among successive sections of a road. So, the operating speed-based method is popularly used for examining design consistency. Numerous studies have been completed on rural two-lane highways for predicting operating speeds. However, little is known for rural four-lane non-freeway highways.
This thesis presents the development of operating speed models for day-time and night-time conditions for highways in Egypt based on a study of 58 horizontal curves at different sites on rural multilane roads. In each horizontal curve, Spot speeds were collected during the day and night at five points. Spot speeds were collected at the middle of first tangent, point of curve, middle of curve, point of tangent and the middle of second tangent.
Statistical tests were used to compare day-time and night-time speeds at the midpoint of each horizontal curve. T-test reveals that there is no statistical difference between daytime and nighttime speeds at the midpoint of the horizontal curves. ANOVA test reveals that there is significant difference in speed variance at the midpoint of the horizontal curves between day-time and night-time conditions.
Another comparison was done to investigate the design consistency of the horizontal curves. Comparison between speeds at the main points of the horizontal curve was made using ANOVA. The results of ANOVA test for horizontal curves showed that there is no significant difference in speeds between each two successive points within the horizontal curve.
In the operating speed models, the radius of the horizontal curve was used to estimate the operating speed. The speed models determined that the operating speed is highly correlated with the radius of the horizontal curve.