The goal of this research project is to evaluate the performance of the crumb rubber test sections compared with the conventional control section and depending on performance, develop Colorado-specific materials and construction specifications for ground tire modified asphalt pavements. Also, the research project aims to develop guidelines and best management practices for the construction of ground tire modified asphalt pavements. Transverse cracking began in the rubber modified sections after 22 months of service and longitudinal cracking began after 29 months. The control sections have no transverse cracking to date with longitudinal cracking beginning to appear after 56 months.
Crack sealing and filling on hot mix asphalt (HMA) pavements are cost-effective pavement preservation techniques that improve pavement performance and extend the life of existing pavements. If performed in a timely and effective manner, crack sealing can extend the life of HMA pavements. CDOT sponsored this study to update its procedures and guidelines for crack sealing and filling of HMA pavements. The draft Guidelines included in this report reflect CDOT experience, current state-of-the-practice, and the most recent research findings, and address where and when to perform crack sealing and filling, material selection, installation methods, construction inspection, and follow-up evaluation.
Thermal Mapping surveys were carried out on approximately 1000 miles of the Colorado Department of Transportations (CDOTs) roads. The purpose of these surveys was to identify road surface variations across the network to determine whether forecast Thermal Maps or the data from the surveys would be useful to decision-makers in the CDOT regions.
The purpose of this study was to quantify the initial design life of a roadways pavement prior to rehabilitation and provide specific performance information through the analysis of pavement management data and historical experience. The analyzed data may be used to estimate the initial life of a pavement which can be incorporated into the LCCA within CDOTs M-E Pavement Design Guide. It will also provide guidance to CDOT and subcontractors in determining the cost-effectiveness of different pavement designs, construction and maintenance costs.
The Winter Performance Index is a method of quantifying winter storm events and the DOTs response to them It is a valuable tool for evaluating the States maintenance practices, performing post-storm analysis, training maintenance personnel, and identifying potential areas of cost savings and improved performance.
The purpose of this study is to evaluate the cost of rehabilitation techniques used on interstates, state highways, and principal arterials dating back to 2009 for use in LCCAs. The rehabilitation techniques used in this study include cold in-place recycling, hot in-place recycling, full-depth reclamation, hot-mix asphalt overlays, hot-mix asphalt mill-and-fill, and portland cement concrete pavement. Hot in-place recycling was further broken into three categories; heater remixing, heater repaving, and heater scarifying.
Self-consolidating concrete (SCC) is a stable and highly flowable concrete that consolidates without the help of external vibration and can flow through heavy reinforcement and around corners in complex formwork under its own weight. The exceptional performance of this remarkable material has attracted the attention of construction firms and DOTs in the United States interested in using SCC on new bridge construction and bridge repair projects.
The objective of this interim report is to provide a synopsis of the progress made after one year on the feasibility of using waste tires (crumb rubber) in the construction of asphalt pavements.
This research is being conducted to evaluate the performance of various preventive maintenance treatments over time and under different environmental conditions to assess the economics of each treatment type.
This research is being conducted to evaluate the performance of various pavement preservation treatments over time and under different environmental conditions to quantify the economics of each treatment type. There are three primary techniques utilized in Colorado for preservation of asphalt pavements and three for concrete pavements.