What are the four primary steps involved in transportation modeling?

• A. Trip Generation, Trip Assignment, Mode Split, Traffic Control
• B. Trip Generation, Trip Distribution, Mode Split, Trip Assignment
• C. Trip Assignment, Mode Condition, Route Planning, Trip Distribution
• D. Traffic Analysis, Route Distribution, Trip Generation, Capacity Analysis

Answer: (B)

The four primary steps involved in transportation modeling focus on understanding and predicting travel behavior to efficiently allocate resources and plan transportation systems. The correct steps are trip generation, trip distribution, mode split, and trip assignment.

Trip generation is the first step, which involves determining the number of trips originating from, or destined to, different zones within a study area. This step is critical because it quantifies travel demand based on factors such as land use, population, and economic activity.

Next is trip distribution, where the trips generated in one area are allocated to destinations in other areas. This is often accomplished using gravity models or other distribution models to consider the attraction of various destinations and the impedance of travel between them.

Following distribution, mode split analyzes how the generated trips are divided among different transport modes (e.g., car, transit, walking). Understanding the preference for various modes helps transportation planners design systems that accommodate different travel needs and preferences.

Finally, trip assignment allocates the trips generated and distributed to the transportation network, determining how many trips take a particular route. This step helps in understanding congestion and the performance of the network under different scenarios.

The other options include steps that either do not form part of the traditional four-step model or combine unrelated concepts that do not accurately