Evaluation The Performance of Al-Thawra At-Grade Intersection Using The HCS2000 Computer Package


Al-Thawra signalized intersection is one of the most important intersections in AL-Hilla city because it relates the Governorates: Baghdad, Najaf, Kerbala and Babel, and serves of about 21000000 passages of vehicles yearly. The excessive traffic volumes, during the peak periods (at morning and evening), of vehicles that entering theintersection increase traffic density, reduce travel speed, increase travel time, and increase the delay values. The delay values are reflected by McTrans Center, University of Florida {Highway Capacity Manual (HCM2000)} to an indicator named LEVEL OF SERVICE (LOS). The operational analysis of the existing conditions of this intersectionby the Highway Capacity Software (HCS2000) indicates that the LOS of it equal to (F) with an intersection delay value of 263.7 sec./vehicle and a degree of saturation exceeds 1.5. Therefore, and because of the reasons above, it is important to improve the performance of Al-Thawra Intersection by separate the conflicting traffic movementswith an overpass bridge. The traffic survey shows that the high traffic volume of through movement of the North-South direction (Baghdad-60St.) has the major effect on the intersection. Therefore, the North-South is the suitable direction to construct the suggested bridge overpass to separate the through traffic of this direction (from Baghdadto Najaf {60 St.} and vice versa) from the other movements of the intersection. The results indicate that the intersection LOS equal (C) with a cycle time of (58) sec. and an intersection delay of (22.8) (sec./veh.) at the object year 2027.