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PMSS Project Details


Project ID:FHWA-PROJ-11-0017
Project Name: Development of the Capacity Analysis for Planning of Junctions Tool (CAP-X)
Status: Completed
Last Name:Lochrane
First Name:Taylor
Office: Office of Operations Research and Development
Team:Trans Ops Concepts and Analysis Team
Project Description:The project will develop a new tool that advances the Alternative Intersections Selection Tool (AIST) to include a new interface, front and back printing for each design worksheet, computer-aided design (CAD) drawn designs, and shared lanes configurations for the conventional intersection. There are three additions that improved from the AIST: (1) The addition of interchanges include diamond, partial cloverleaf, displaced left turn double crossover diamond, and single point. (2) The addition of one lane by two lane and two lane by one lane roundabout configurations with the 2010 Highway Capacity Manual (HCM) capacity equations.(3) The addition of the mini-roundabout model for 50-foot and 75-foot inscribed circle diameter designs.
Laboratories: Saxton Transportation Operations Laboratory
Start Date: March 7, 2011
End Date: March 30, 2012
The key project objectives are:
(1) Upgrade the interface and improve the use of the tool.
(2) Add new innovative interchanges and roundabout designs.
(3) Release the tool.
Test Methodology: Critical volumes calculated in Excel.
  • Federal Highway Administration: Office of Research, Development, and Technology - Office of Safety Research and Development; Role(s): Advisory
  • Federal Highway Administration: Office of Operations - Office of Transportation Operations; Role(s): Advisory
  • Federal Highway Administration: Office of Operations - Office of Transportation Operations; Role(s): Advisory
Expected Benefits:The expected benefit is a tool that will help traffic planners evaluate innovative intersection designs.
Deliverables:Name: Capacity Analysis for Planning of Junctions (CAP-X)
Product Type(s): Software
Description: The new version will include roundabouts and new innovative interchanges.
Publication URL(s):
Keywords: Transportation Planning
Geometric Design
Types of Intersections
Highway Traffic Control
Subject Areas: Planning and Forecasting
Operations and Traffic Management