ABSTRACTAn operational analysis is an analytic evaluation of operation on an existing freeway ramps. In this case, all traffic and roadway conditions must be specified. The output of operational analysis is an estimate of the level of service for the ramp in question and of the approximate speed and density at which the traffic stream operations.A ramp is length of roadway providing an exclusive connection between two highway facilities. On freeways, all entering and exiting maneuvers take place on ramps those are designed to facilitate smooth merging of on-ramp vehicles into the freeway traffic stream and smooth diverging of off-ramp vehicles from the freeway traffic stream onto the ramp.The aim of this paper is the operational analysis of ramps on existing 6-lane freeway. This analysis involves the consideration of known freeway of Mohammed Al-Kasim freeway in Baghdad city. Given known geometric roadway conditions and projected traffic conditions, the operational analysis yields an estimate of the level of service and of the speed and density of the traffic stream. This paper has described the procedure for determining the level of service on Mohammed Al-Kasim freeway ramp sections as presented in the Highway Capacity Manual (HCM, 2000). Levels of service are determined for all ramps of the freeway using )HCS2000( software. Level of service of all ramps are similar at AM and PM peak hour periods, because the data was collected under ordinary traffic conditions.
Traffic engineers frequently are engaged in evaluating the performance of different facilities of the highway system. The facility in this project includes freeway section. In design of a freeway, a forecast demand volume is used with known design standards for geometric features and a desired level of service to compute the number of lanes required for the freeway section in question. The design application is straight forward for each usage, but trial-and- error operation analysis may be required to evaluate alternative design. Design requires a detailed traffic forecast, including volumes, peaking characteristics, traffic composition, and specifics of vertical and horizontal alignment for the section under study. The aim of this paper is the design analysis of a freeway with a heavy recreational vehicles. This analysis involves the consideration of three examples of freeways. Given known geometric roadway conditions and projected traffic conditions , the design analysis yields an estimation of the number of lanes and of the speed and density of the traffic stream. This paper has described the procedure for determining the number of lanes of freeway basic sections as presented in the Highway Capacity Manual (HCM, 2000) and HCS2000 software.
Traffic control devices notify road users of regulations and provide warning and guidance needed for safe, uniform, and efficient operation of all elements of the traffic stream. Traffic control devices have been a part of the roadway system. Researches have evaluated various aspects of the design, operation, placement, and maintenance of traffic control devices. The purpose of this research is to develop a simulation model in order to evaluate the effect of overhead sign position on the traffic performance at exit of freeway weaving area. To achieve that subroutine was developed and added to FWASIM program to compute the sign position and compare it with the driver sight distance. Following that a proposed example represents an exit weaving area was examined with different traffic flow configuration (different percentages of link flow and on-ramp flow) with respect to no sign installed and other three sign positions. Results indicate that the average traffic speed is underestimated when there is no sign installed, while no significant effect is shown when the sign position is changed within the driver sight distance. In conclusion Guide signing is a critical element in the effective, efficient and safe operation of motorways and expressways. Signing issues must, therefore, be fully considered at the feasibility stage of any project.