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⢠The tools need modifications to support scenario analysis. These modifications should include the ability to designate specific time periods and highway segments for analysis. Practitioners need the ability to tailor reliability analyses to support existing studies and analysis. In addition, tool users need to be able to adjust time periods and highway segments and then rerun analyses without having to set up the models from scratch. ⢠A related need is the ability to import and save data. The reliability tools tested in the Southern California pilot site needed varying amounts of data, but generally required the user to enter information through pull-down menus or manual entry. For the tools that require large amounts of information (e.g., FREEVAL-RL), the ability to copy and paste data or import data from external spreadsheet files would significantly aid the calibration and scenario processes. ⢠The tools also need analytics to support specific types of operational improvements. For Southern California, the most common operational projects to test include ramp metering strategies, auxiliary lanes, freeway connectors, and ramp modifications. The other three pilot sites may identify additional project types. The SHRP 2 reliability tools should be able to analyze the projects that users are most likely to want to test. ⢠The tools need to be able to model reliability for highly congested facilities. Practitioners most likely will want to test reliability on these facilities, yet the extent and duration of congestion in Southern California exceeded the ability of some SHRP 2 tools to model congestion. ⢠The tools need to support life-cycle benefit analysis. Benefit-cost analysis needs the sum of user benefits over an expected life cycle. The current tools either estimate benefits for specific years or assume that the current benefits remain constant over the life cycle. The tools should be modified so that agencies can simply take the sum of the reliability benefits and add them to standard benefit-cost analysis. Reliability Performance Measures Common reliability performance measures should be used across the planning process. The SHRP 2 reliability research has resulted in different measures and tools, but inconsistency can result if they are applied to a practical planning problem. Figure ES.8 summarizes a simple planning process and the inconsistency in measures when the SHRP 2 tools are applied. 13
