traffic-flow-dynamics.org/traffic-states

Help for using the search functionality

Notice: All the following relates to the search mask on the left-hand side.

Route

After selecting the Highway and the (driving) Direction, the search mask for a section becomes active. At present, the data base containes spatiotemporal speed profile of the German freeway A5 for the driving directions North and South.

Notice that the morning rush hour produces traffic jams mainly in the southern direction, while the afternoon rush hour mostly affects the direction to the north.

Time

You can select the period by indicating the first day ("from") and the last day ("to"). Additionally, you can filter with respect to days (of the week), and the daytime (morning, afternoon, whole day).

Notice that similar patterns are often observed on same days of the week.

Traffic Pattern

The congestion images are discriminated with respect to the elementary spatiotemporal patterns which can be organized in a so-called dynamic phase diagram . One instance of a congestion may contain several elementary patterns. The patterns and their searchable abbreviations are the following:

MLC: Moving Localized Cluster

Isolated moving jam waves.

PLC: Pinned Localized Cluster

Isolated standing waves that are fixed, or pinned, at a bottleneck. This type of pattern typically occurs if the traffic demand is too low for causing an extended congestion such as TSG, OCT, or HCT.

TSG: Triggered Stop-and-Go

Moving jam waves emanating from a localized or extended zone of essentially stationary congested traffic near the bottleneck.

OCT: Oscillating Congested Traffic

Extended congestion with distinct internal traffic oscillations. The TSG and OCT states are also referred to as stop-and-go traffic.

HCT: Homogeneous Congested Traffic

Homogeneous and stationary "creeping traffic" which typically occurs behind strong bottlenecks such as lane closings and accidents. This includes the trivial case of completely stopped traffic behind a complete road closure (or a red traffic light).

Further comments

Each image includes a documentation about the specifics of the corresponding congestion (see this example). The text of this documentation is searchable by the full text search box. Some relevant keywords are the following (for further keywords, just look at some documentation fields):

  1. moving bottleneck
  2. accident
  3. mega-jam
  4. complex
  5. special
  6. MLC / PLC/ TSG / OCT / HCT / HST