11.3.2 Stage 1 Operational Performance and ICE
CAP-X is a Stage 1 ICE spreadsheet-based tool that compares anticipated v/c ratios of various interchange and ramp terminus types. CAP-X analysis determines the interchange type that will provide the most capacity given a set of inputs. CAP-X analyzes multiple intersection types. CAP-X covers initial screening of the following types of interchanges:
- Diamond;
- Partial cloverleaf A and B;
- Displaced left-turn;
- Contraflow left;
- DDI;
- SPUI; and
- Single-point roundabout
CAP-X screens most types of interchanges except for the double roundabout interchange. CAP-X is typically used for initial screening of interchanges, but not for ranking alternatives – just a pass/fail indication. Any additional analysis on interchanges is done in HCM-based (mesoscopic), deterministic, or microsimulation (microscopic) tools. An example output of CAP-X is shown in
Appendix K, Section 4 – Sample Output
.