Framework of calculating the measures of resilience (MOR) for intermodal transportation systems.

PDFTech ReportFHWA/MS-DOT-RD-10-220State Study 220Intermodal transportationResilienceMississippiMississippi. Dept. of TransportationZhang, LiWen, YiHuang, ZhitongJin, MingzhouMississippi State University. Dept. of Civil and Environmental EngineeringUnited States. Federal Highway AdministrationMississippi. Dept. of Transportation. Research DivisionUS Transportation CollectionRecent catastrophic events, such as Hurricane Katrina, have accentuated the value of measures of resilience (MOR) for the response andrestoration of transportation systems following a disaster and have therefore become a topic of great concern for transportation researchers.However, according to a review of current literature, a widely accepted method for evaluating MOR for transportation systems (especially in anintermodal context) has not been established. The objective of this report is to develop a framework for MOR calculation for intermodaltransportation systems in response to disaster and to evaluate effectiveness of strategies for improving the MOR. Freight transportationresilience is the main concern in this report; however, to replicate actual traffic conditions, passenger transportation is also considered as a partof an integrated transportation system. For the MOR calculation procedure, TransCAD was used to model the research area network andgenerate transportation data. Pre-disaster and post-disaster population and employment data was collected at the county level and disaggregatedto each Traffic Analysis Zone (TAZ) using linear equations. Then, based on the study area\ue2\u20ac\u2122s population and employment data, the networkOrigin-Destination (OD) traffic before and after the disaster was estimated using TransCAD. A series of resilience indicators in terms ofmobility, accessibility, and reliability were selected to evaluate the intermodal system performance based on the TransCAD outputs. APerformance Index (PI) is further introduced which aggregates several resilience indicators to measure system performance regarding mobility.The Level of Service (LOS) of highway networks and intermodal terminals before and after a disaster were also determined according to theirrespective LOS standards. Based on these resilience indicators, MOR in this report is defined the percentages of system performance measuresdegraded. A formula was developed to produce quantitative values for intermodal system MOR with respect to mobility, accessibility, andreliability. The above process was reviewed in a case study of the Mississippi Gulf Coast region. The analysis demonstrated the effectiveness ofthe proposed MOR calculation procedure. In addition, strategies for improving MOR were studied, and because the impact of disaster to MORwas not significant, rerouting was proposed as a method for improvement. To evaluate the effectiveness of rerouting, experiments wereexplored using DynusT simulation. Results of this experimentation show that, in this case, rerouting is a valid method for MOR enhancementand that diversion delay is significant