Speed Policies and Guidelines For The Urban Roadway Network in Al-Ramadi City

Abstract

This paper represents a Free-flow speed (FFS) parameter that is being used extensively for capacity and level-of-service analysis of various types of highway facilities. As a first effort in the trial of developing local highway standards and guidance for Ramadi city, this study collects and analyzes FFS data at eight roadways in Ramadi city. The objectives of this study are to develop models for estimating average FFS and to set posted speed limit designations. The obtained models reflect the most important variables that govern the FFS,which includevehicle type, speed limit, and shoulder type. A regression model was also developed to predict the relationship between the average running speed (ARS) and the traffic volume. The proposed value of a posted speed limit wasfound to be 80km/h, while the recommended design speed for the Al-Ramadi network is 90km/h.

Keywords

• Free-flow speed,speed limit,design speed,guidelines

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