Following a rigid set of testing protocols, data is being collected on highway traffic noise characteristics along with safety and durability aspects of the associated pavements. This report completes a comprehensive, long-term study to determine if particular pavement surface types and/or textures can be used as quieter pavements, and possibly be used to help satisfy FHWA noise mitigation requirements.
This report presents information and data produced by the Colorado Department of Transportation's long-term study of Portland cement concrete pavement (PCCP) textures used within the state. The information includes vehicle accident, friction, and texture data. This information was used as the for a review of proposed revisions to the CDOT texture measurement method, CP-77, and a specification for PCCP texturing found in Sections 106 and 412 of the Standard Specifications.
The results from the research study suggest that there is a clear demand to incorporate real-time weather conditions and roadway geometric characteristics within the development of the ATM system. This model has the potential to be an accurate component of a proactive traffic management strategy to provide reliable and timely information to drivers under various adverse environments. This work could serve as the basis for a future Variable Speed Limit algorithm to be deployed on I-70.
This study applies contract bid tabulations and element-level condition records to develop element-level actions, costs for actions, transition probabilities for models of deterioration of bridge elements, and transition probabilities for improvements to elements due to actions. The study uses transition probabilities for element deterioration to compute the number of years to possible loss of safety in bridges, and to compute the number of years for inspection intervals. It examines variations in costs of actions and deterioration of elements among CDOT regions.
Adaptive signal control uses real-time data collected by system detectors to optimize signal timing for each intersection in the corridor. The use of real-time data means that signal timing along the corridor changes to accommodate the traffic patterns at any given time of the day. Test systems were set up in Greeley and Woodland Park, Colorado.
The goal of this project is to investigate the hydraulic efficiencies of Type 13 (bar inlets), Type 16 (vane inlets), and Type R (curb-opening inlets) for street and roadway drainage. Although these inlets have been widely used in many metropolitan areas, the design empirical formulas and coefficients have not been verified.
Roller Compacted Concrete (RCC) is a no-slump concrete mixture that is transported, placed, and compacted with the same construction equipment as asphalt pavement. After only nine months of service, the RCCs already showed noticeable changes in all of the selected properties tested. More tests and field inspections should be conducted in the future after a longer monitoring period to verify and validate the initial findings observed in the material properties and surface conditions of the RCC pavements.
In this study, the Regional Transportation District's (RTD's) light rail tracks were modeled to determine the Rational Method runoff coefficient, C, values corresponding to ballasted tracks. The runoff coefficient for ballasted tracks is significantly larger than the previously tabulated values for railroad yards. The higher runoff coefficient reflects the design of ballasted tracks to drain rainfall as quickly as possible.
