Forum > Developing Inputs > Which ITS treatments does RPAT take into account?
What specific treatments should the ITS policy measures encompass? For arterials does it include interconnected signal systems? Adaptive signal systems? Integrated corridor management? For interstates: ramp metering (if so, how to measure in miles of treatment?), emergency service patrol areas, VMS/CCTV? How should we hand hard shoulder running projects? (Shoulders used as through lanes during peak hours). Are they ITS improvements or additional lanes? What about emergency service patrols? If they are included, how much service does an ESP need to qualify (full day, peak-hour coverage, etc.?). What about highway segments that have multiple types of ITS (such as ESP and VMS/CCTV or ramp metering)?
or Log In
Replies
The ITS policy measures the effects of incident management supported by ITS. The ITS table is used to inform the congestion model and the travel demand model. The model uses the mean speeds with and without incidents to compute an overall average speed by road type and congestion level providing a simple level of sensitivity to the potential effects of incident management programs on delay and emissions. For more information see the section on ITS Policies in Appendix B of the SHRP 2 C16 report.
Items to note for determining how to account for ITS policy measures:
1. The ITS treatments that can be evaluated are those that the RPAT user considers will reduce non-recurring congestion due to incidents. This policy does not deal with other operational improvements such as signal coordination, or temporary capacity increases such as allowing shoulder use in the peak.
2. The ITS treatments are evaluated only on freeways and arterials.
3. The model is a scenario testing model: it does not explicitly represent particular policies and simulate their behavior, rather the user asserts that the individual policy or group of policies will reduce non-recurring congestion due to incidents on a percentage of the highway system and then the model calculates the impact of the reduction in reduce non-recurring congestion.
To reply, please login.