Modeling Approach for AMS Phase 2

Essential elements of the modeling approach for AMS Phase 2 are described below. Further details, including the considerations involved in choosing an approach and how the selected approach impacts modeling efforts, can be found in the AMS Phase 2 presentation.

Purpose of the model

The purpose of the model is to:

  • Understand how to manage incidents on the I-210 corridor
  • Take account of short-term traveler responses such as en route diversion triggered by unusual congestion or information dissemination
  • Guide the assembly and selection of appropriate response plans for potential deployment
  • Evaluate performance

Geographic scope

The model is focused primarily on the  the freeways and main arterials in Pasadena, Arcadia, Monrovia, and Duarte. In addition, however, the model has been extended to include:
  • Modeling of the I-210 freeway to Azusa to adequately capture bottlenecks
  • Modeling of key arterials outside the main area of interest to capture routing behavior that may affect corridor operations

Possible simulation approaches

The Connected Corridors team considered various simulation approaches for AMS Phase 2:

Approach
Description
Microscopic
  • Modeling of individual vehicles
  • Complex car-following and lane-changing models
Mesoscopic (micro-based)
  • Modeling of individual vehicles or groups of vehicles
  • Simplified car-following model
  • May or may not include lane modeling
Mesoscopic (macro-based)
  • Behavior based on deterministic relationship between flow, speed, and density
  • More detailed link-node representation than macro models (example: CTM model)
Macroscopic
  • Behavior based on deterministic relationship between flow, speed, and density
  • Simple link-node network representation

Selected simulation approach

The approach selected for AMS Phase 2 is a hybrid simulation in Aimsun:
  • Microscopic simulation for the mainline freeway, freeway ramps, and some arterials
  • Mesoscopic simulation for the remainder of the network