Microscopic Model of Road Capacity for Highway Systems in Port Based Metropolitan Areas

Disclaimer The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Transportation assume no liability for the contents or use thereof. The contents do not necessarily reflect the official views or policies of the State of California or the Department of Transportation. This report does not constitute a standard, specification, or regulation. Abstract In this report, we present our approach to use microscopic modeling to assess highway traffic mobility during lane blockage situation. A test microscopic model using ARENA software is developed. In this model, we specifically aim to simulate the impact of container trucks on highway traffic capacity and risk of accident during lane blockage. The test model simulates a 3000 feet distance on a two lane highway, while the passing lane is blocked at 2500 feet distance from the beginning. Merging sign and taper zone was used to guide traffic on the passing lane to merge to driving lane. We adjust the cargo truck traffic ratio to assess the effect of cargo trucks on the road mobility. The road mobility is assessed using the throughput ratio (total number of vehicles exited the system/ total number of vehicles entered the system). The risk of collision is assessed using the number of unsuccessful merging attempts at the taper end. Traffic throughput and risk of collision is simulated as a function of traffic density, cargo truck percentage as well as number of merging signs placed onsite. We found that: 1) Increasing traffic density significantly reduces the road throughput, while increases the risk of collision moderately too; 2) Increasing cargo truck percentage reduces road throughput, while increases the risk of collision; 3) Increasing number of merging signs increases the traffic throughput and reduces the risk of collision up to a threshold. Under the traffic condition we studied, this threshold is two merging signs.