الفهرس 
Road Geometric DataOnly 14 pages are availabe for public view
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Abstract
Multi-lane highways symbolize the plurality of the overall length of highway network in Egypt. The road geometry and the percentage of heavy vehicles (HV) are counted the most serious factors that affect level of service (LOS), capacity, and free flow speed (FFS) for any roadway. Subsequently, this study aims to discuss the relationship between the road geometric characteristics and HV, and LOS, capacity, and FFS by statistical modeling. The modeling is divided into two models. First is the modeling for LOS, capacity, and FFS on one direction of flow and second is the modeling for LOS, capacity, and FFS on right lane. In this study, the road geometric and traffic data are collected from straight section at 28 various sites that are located in desert highways. These sites are separated into 14 sections in divided four-lane roads, 7 sections in divided six-lane roads, and 7 sections in divided eight-lane roads. The results showed that the statistical modeling gives models with high R2 (coefficient of determination) and low ǁδǁ (percent error) values for estimating LOS, capacity, and FFS, in both cases. On one direction, the most influential variables on LOS and capacity in all sites are number of lanes (NL) and median width (MW) respectively, while the most influential variables on FFS in all sites are HV, followed by pavement width (PW). On right lane, the most influential variables on LOS in all sites are HV, followed by NL, then lateral clearance (LC), the most influential variables on capacity in all sites are HV, followed by MW, and the most influential variables on FFS in all sites are HV, followed by LC, then MW. These results are so important for road authorities in Egypt as they can determine capacity for different straight sections and improve the traffic performance of them in the future.