I-66 Multimodal Study Final Report - Virginia Department of ...

Mobility OptionsModel Process for Testing Mobility OptionsThe mobility options were assessed using an abbreviated application of the TPB model toeconomize the time required for producing the model outputs used in the mobility optionevaluation. The following provides an outline of how the options were tested and is showngraphically in Figure 2.2.The CLRP+ Baseline was run through the full model process to produce trip tables for usein the abbreviated model process. This included a“pump prime” iteration and then fouriterations of the model back through the model steps.The final (fourth) iteration person trips from the full CLRP+ run were then used as inputs tothe abbreviated test process for each option, which used only a single iteration.The abbreviated process ran the CLRP+ trip tables through the mode choice and assignmentsteps using the build network for each option. For each option tested, the highwayand transit networks were rebuilt and travel times calculated from these networks. Sincethis process only performed a single iteration, the final loaded networks with the congestedtravel times were not fed back into the trip distribution or mode choice models.The abbreviated process also was performed on the CLRP+ network in order to provide aBaseline scenario for comparison.The purpose of this abbreviated process was to identify positive and negative aspects for eachoption so that winning strategies could be carried forward in the multimodal packages. Basedon the abbreviated model process, the mode choice results were produced using non-congestedspeeds in the highway skimming process. Additionally, without the speed feedback to tripdistribution, the model outputs do not reflect changes in travel patterns which might result inthe corridor with the inclusion of each mobility option.I-66 Multimodal Study 2-9