Traffic Operations and Management

We propose a methodology for identifying queue spillovers in city street networks with signalized intersections using data from conventional surveillance systems, such as counts and occupancy from loop detectors. The key idea of the proposed methodology is that when spillovers from a downstream link block vehicle departures from the upstream signal line, queues discharge at rates smaller than the saturation flow. The application of the methodology on an arterial site and the comparison with field data show that it consistently identifies spillovers in urban networks with signal-controlled...

This report investigates how Caltrans may incorporate third-party vendor data into its established system for performance measurement to improve accuracy of vehicle hours of delay (VHD) estimates and to enable smarter deployment of point-based sensors, such as loops. Methods are evaluated to project data from multiple sources, including multiple vendors and internal data feeds, onto the same domain of analysis so as to compute performance metrics with high fidelity. The recommended VHD estimation method depends on the infrastructure type and the data available. Overall a hybrid approach...

The past few years have seen a rapid evolution in the sophistication of traffic microsimulation models and a consequent major expansion of their use in transportation engineering and planning practice. Researchers and practitioners have employed an extensive array of approaches to calibrate these models and have selected a wide range of parameters to calibrate and a broad range of acceptance criteria. A methodical, top-down approach to model calibration is outlined; it focuses the initial effort on a few key parameters that have the greatest impact on model performance and then proceeds to...

This Guide provides a conceptual analysis framework, recommended measures of effectiveness, and an initial recommended methodology for evaluating the impacts of Active Transportation and Demand Management (ATDM) strategies on highway and street system demand, capacity, and performance. The Guide presents practitioners with methods to analyze the varying demand and capacity conditions that facilities operate under and methods to apply a limited but broad set of transportation management actions to respond to those conditions. Thus, the methodology represents, in a macroscopic sense, the...