A partial restriction is entered on a segment or a turn restriction. A partial restriction is often referred to as a time-based restriction (TBR); specifically as a time-based segment restriction (TBSR) or time-based turn restriction (TBTR). They are used to allow or to restrict certain vehicle types to be routed or prevented from routing on that segment or turn. The TBSR or TBTR means the segment or turn will tell the routing algorithm that some vehicle type(s) are forbidden or allowed on a segment or turn; or some or all vehicles are forbidden at certain times, or on certain days or dates, or both; that certain special types of travel are allowed.
Note currently only private car and taxi are allowed to be selected in the app; therefore restrictions preventing trucks or buses from a segment or turn do not have any affect in the app. Setting a segment to be a bus only segment will prevent any user from being routed and is the equivalent of a prohibited all private cars and taxi restriction.
Partial restrictions are often used for bus lanes, turns that are forbidden during rush hour, segments that change direction for morning and evening rush hour, bridges and ferries that are only available during the day, and roads that are closed in winter.
If a turn is forbidden on all days, dates, and times, then use turn restriction or if the segment never allows travel in that direction then one-way road instead. If no traffic will ever be allowed to travel through an intersection, it should be disconnected. If no traffic will ever be allowed to travel on a segment, the segment should not be added to the map.
In some cases, the turn (typically left-hand) may simply be difficult to make at certain times of the day due to uncontrolled intersections during heavy traffic periods. The difficult turn should not be installed where there is a traffic light or a dedicated left turn lane.
For big road-closing events such as marathons and parades, please see Mega events For construction-related traffic closures, please see Real time closures.
Overview
This article covers how to create scheduled restrictions and vehicle type restrictions. Collectively, these can be termed Partial restrictions.
Partial restrictions can be based on:
- An entire segment controlling traffic flow for one or both directions TBSR
- Specific turns from one segment to another TBTR
Each of these restrictions can be further restricted based on combinations of:
- Vehicle type (trucks, buses, hazardous materials, etc.)
- Time of day, day of week, and date range.
Examples:
- No left turn 7a-9a and 4p-6p weekdays
- HOV lanes eastbound 5a-11a, westbound 3p-10p
- Flexible capacity lanes which are a single roadway, but run a different direction for morning and evening commutes (frequently found on congested freeways and some primary streets, sometimes with limited exit or turn options to create express traffic routes)
- Interstate truck-only ramp (not used in app at this time)
- No trucks allowed between 9a-3p weekends (not used in app at this time)
- Vehicle towing a trailer (not used in app at this time)
While this is a very flexible system, it can be a complex interface to manage the many combinations possible. It is certainly very important that any changes made to any current scheduled restrictions on the map be done with extreme caution so as not to destroy hours of work by prior map editors. Therefore be sure to only make changes to scheduled restrictions with careful consideration and patience.