Transportation Planning and Travel Demand Modeling
Map of trip attractions created with TransCAD transportation planning software
Trip distribution map created with TransCAD transportation planning software
AM Peak Traffic Assignment and VOC Map created with TransCAD transportation planning software
Transportation planning and travel demand models are used to predict changes in travel patterns and the utilization of the transportation system in response to changes in regional development, demographics, and transportation supply. TransCAD is the only planning package that is GIS-based and fully integrates GIS and planning tools for trip generation, trip distribution, mode split modeling, and traffic assignment. TransCAD includes all of the traditional UTPS models, quick response models with reduced data requirements, and advanced disaggregate demand models.
Trip Generation/Production models included with TransCAD estimate the number of trips, by purpose, that are produced or originate in each zone of a study area.
Trip Attraction models predict the number of trips attracted to each zone or to a particular land use.
Trip Balancing methods are provided so that the number of attractions equals the number of productions.
Trip Distribution models are used to predict the spatial pattern of trips or other flows between origins and destinations.
Mode Split models are used to analyze and predict the choices that individuals or groups of individuals make in selecting the transportation modes that are used for particular types of trips.
P-A to O-D and Time of Day tools enable you to convert productions and attractions to origins and destinations, decompose a 24-hour trip table matrix into hourly trip tables, convert person trips to vehicle trips, and apply peak hour factors.
Traffic Assignment models estimate the flow of traffic on a network and allow you to establish the traffic flow patterns and analyze congestion points. TransCAD provides a full complement of traffic assignment procedures that are used for modeling urban traffic. These procedures include numerous variants that are tailored for modeling transit, as well as intercity passenger and freight traffic by rail, road, air, and barge.
Advanced Highway Assignment procedures included with TransCAD allow for generalized-cost traffic assignment, HOV assignment, multimode vehicle assignment, multiple user class traffic assignment, combined trip distribution/assignment, and assignment with volume-dependent turning delays and signal optimization.
There is a new master, multimodal equilibrium traffic assignment procedure that simultaneously assigns cars, trucks, and buses to the road network. There can be multiple user classes for cars (e.g. HOV users) as well as different classes (e.g. sizes) of trucks. This procedure includes the option of using exact entrance to exit tolls by vehicle class and differential values of time to be used in calculating generalized cost. Network exclusions keep each class of traffic restricted to the links that it is permitted to use. Some vehicles, such as fixed-route buses, can be pre-loaded on the multimodal network. Among the reporting options is a breakdown of link traffic by vehicle class and type.