Impact of Lane Closures on Roadway Capacity, Phase 2

This project is a follow-up to Florida Department of Transportation (FDOT) research project BD545-61, “Impact of Lane Closures on Roadway Capacity” (specifically, Part A: Development of a Two-Lane Work Zone Lane Closure Analysis Procedure and Part C: Modeling Diversion Propensity at Work Zones). In this previous project, the primary objective was to update the procedure in the Plans Preparation Manual (PPM), Volume 1, Section 10.14.7 (2006), for two-lane roadways. Field data collection was not included in the previous project; thus, the results were based strictly on simulation data from the FlagSim simulation program.

The primary objective of this project was to update the two-lane roadway with a lane closure analysis procedure developed under the previous project, based on calibrating the FlagSim simulation program to field data. An additional aspect of this that was not considered in the BD545-61 project was to account for the effect of grade on the work zone performance measures. An additional project objective was to update the RTF estimation method developed under the BD545-61 project, as necessary, based on measured traffic demands (before and during) at work zone field sites.

Field data were collected at three sites and used to calibrate the FlagSim program. FlagSim was then used to generate the data used to update the models contained in the analysis procedure developed under the previous project.  Local area traffic demand data were also used to update the RTF estimation model.