Effects of Signal Optimization vs Signal Free Corridor in a Network (Chairing Cross to Katchery Chowk Rawalpindi)

Abstract

Pakistan is a country with diverse transportation system. In last decade rapid increase in motorization population is experienced due to commercial and globalization activities. Also people from villages migrate towards cities at large scale, which resulted into urban sprawl and traffic congestion. On the other hand transport structure is aging in large and well known cities of Pakistan and unable to meet the existing traffic demand. Which demand a well planned, efficient transportation system to ensure better operational condition and mobility of roads. A study is conducted to identify traffic congestion problems for existing and forecasted traffic conditions, the corridor of National Highway N-5 in Rawalpindi from Katchery Chowk to Chairing Cross was selected. There are eight signalized intersections in this corridor. Te corridor selected is one of the busiest in Rawalpindi city. PTV Vistro and PTV Vissim were used to analyze the corridor for different conditions.PTV Vistro gave us results in the form of approach LOS, intersection LOS, approach delays, intersection delays, and V/C ratios for each intersection. On the other hand PTV Vissim gave us the results in the form of delays, travel times, fuel consumption and vehicle emissions. A pragmatic approach and chronological methodology was followed for the accomplishment of objectives of study. The first step was selection of the study area. After selection of corridor traffic volume data, intersections geometric features and signal timings were also recorded. Analysis of traffic data using the appropriate traffic engineering softwares (PTV Vistro and PTV Vissim) was conducted. The analysis performed by the software was not limited to only existing/current scenarios but was broadened out to include future projected values for improved as well as unchanged scenarios. The intersections were evaluated keeping in view of following scenarios: (1) Existing condition (Pretime condition) without any optimization/ coordination of signals for year 2016 and 2030, (2) Signal coordination was performed where intersections are in close vicinity using PTV Vistro for the year 2016 and 2030, (3) Signal optimization in Pretime conditions using PTV Vissim for year 2016 and 2030, (4) Signal free corridor using PTV Vissim for the year 2030. Keeping in view the results obtained from analysis it was found that signal coordination and optimization are valid in the year 2016 but not in year 2030, so it is not a long term solution. Grade separation in the form of underpasses was also envisaged on some intersections as the traffic conditions were feasible for the construction of such structure. XIX The plans aimed at smoother traffic progression and acceptable LOS’s by reducing delays, as well as lowering fuel consumption which would in turn reduce the harmful emissions into the environment, minimizing the impact of this road segment will have on the environment in general. These plans, if implemented and led to fruition by the concerned authorities would provide road users with a general peace of mind associated with a smoother traffic flow, reduced emissions and minimal bottlenecks and a corridor convenient as well as economical to travelers.