Network construction congestion cost (NCO(3)) model: A method of estimating the impacts of work zones in road networks

Construction work zones often create delays and aggravate road users. The literature includes several models that have been developed to estimate work zone impacts on road users. However, these models calculate the impacts only on road users who normally travel the work zone route, and they do not include impacts on road users who normally travel alternate routes.; This research has developed a new model called the Network Construction Cost Congestion Cost (NCO3) model is developed. By analyzing traffic at the network level, NCO3 estimates cost impacts of multiple work zones on all road users in a network, including those who travel alternate routes. NCO3 determines traffic disruption cost as the sum of additional cost to all road users in a road network due to the existence of work zones. The additional cost differs from road user to road user, depending on the travel choice each selects during construction. Road users are categorized into five groups: road users who keep the same schedule and route, users who keep the same schedule but divert to other routes, users who shift time by one hour, users who reschedule trips, and users who cancel their trips. Rather than using a single criterion such as travel time or cost, NCO3 models the behavior of road users using Travel Impedance Function, a value system that captures all factors that influence road users' decisions, including those that cannot be specifically identified. NCO 3 estimates one-hour time shifts, trip reschedules, and trip cancellations using concepts similar to market equilibrium and demand-supply curves in micro-economics based on travel impedance rather than product cost. In estimating route diversions, NCO3 applies User Equilibrium theory and network assignment techniques using travel impedance as the route selection criterion. Three advanced features are introduced to accommodate real traffic situations. Imbalance models traffic that is not in equilibrium. Initial gap cap models the traffic situation where the number of alternate routes increases with the amount of travel delay. Sink captures a situation of a route having a maximum delay threshold.; The NCO3 has been implemented in software. This software is built on a Microsoft Excel-based spreadsheet and uses a program written in Visual Basic to perform the iterative calculations.