Search results
(141 - 156 of 156)
Pages
- Title
- State Highway 9 wildlife crossings mitigation monitoring
- Abstract
- This research monitored the effectiveness of a wildlife mitigation project on SH 9 in Grand County Colorado. The purpose of the mitigation was to reduce wildlife-vehicle collisions while providing permeability for wildlife across the highway. was designed to improve driver safety while allowing for wildlife movement across the road. This study uses motion-activated cameras and WVC crash and carcass data to determine how successful the mitigation measures are.
- Date
- 2021
- Title
- Polyethylene pipes for use as highway culverts
- Abstract
- The first Colorado Department of Transportation (CDOT) installation of polyethylene pipes for culvert use was in 1988, on SH 50, north of Olathe. Five to ten feet of well compacted in-situ material was used as backfill. No obvious deflections occurred in the pipe during or after construction, or as a result of in-service live loads. After three years of service, the pipes have not cracked, melted, or worn, and are in good overall condition. One culvert, however, burned for about ten feet into one end as a result of the ignition of sawdust that had collected in it from a nearby sawmill. This section of pipe was replaced. A literature search found that with proper backfill, loads of 100 ft of fill could safely be supported. Some pipes, however, were reported to have deformed excessively even with small loads. These were for the most part 12 in. and 15 in. diameter pipes that had a thinner wall, and were not well supported. The main advantages of polyethylene pipes are: light weight, easier installation, corrosion resistance, and relatively good aesthetic qualities. Plastic pipe is a current option for use in the 1991 Colorado Standard Specifications. In most cases it will be left up to the contractor to determine which pipe material to use to meet the specifications for each particular project. Adequate wall thicknesses and corrugations should be specified. Only Class 1 or better material, compacted in thin lifts to 95% maximum density, should be used. Extra care should be taken to compact under the haunches. With care, fills of at least 50 ft are possible.
- Date
- 1991
- Title
- Investigation of mechanistic deterioration modeling for bridge design and management
- Abstract
- The ongoing deterioration of highway bridges in Colorado dictates that an effective method for allocating limited management resources be developed. In order to predict bridge deterioration in advance, mechanistic models that analyze the physical processes causing deterioration are capable of supplementing purely statistical models and addressing limitations associated with bridge inspection data and statistical methods. A review of existing analytical models in the literature was conducted. A mechanistic model was developed to predict corrosion and concrete cracking as a function of material and environmental inputs.
- Date
- 2017
- Title
- Synthesis report on the use and design of snow sheds to protect transportation corridors against avalanches
- Abstract
- This report provides a synthesis on the use and design of snow sheds to protect transportation corridors against avalanches. This report summarizes the various snow shed designs and standards, regulation environment, construction and operational costs, risk, benefits, loading considerations, operational and design considerations, and alternate methods employed when snow sheds are no longer needed, or when alternative long-term mitigation measures are employed.
- Date
- 2020
- Title
- Emergency escape ramps (EER) improvements
- Abstract
- The objective of this research is to develop a set of design and operational recommendations to reduce the number of rollover, jackknife, and rollback end positions for trucks entering the emergency ramp. The products of this research is a series of recommendations focusing on: a) maintenance/material replacement, b) signage and pavement marking, c) shoulder strengthening/widening, d) new construction, e) lighting, and f) drivers' outreach.
- Date
- 2018
- Title
- State Highway 9 wildlife crossings monitoring, year 2 progress report : December 2015 through April 2017
- Abstract
- This research evaluates the effectiveness of the SH 9 Colorado River South Wildlife & Safety Improvement Project, including two wildlife overpasses, and five wildlife underpasses connected with 10.4 miles of wildlife exclusion fencing in Grand County, CO. The project was designed to improve driver safety while allowing for wildlife movement across the road. This study uses motion-activated cameras and WVC crash and carcass data to determine how successful the mitigation measures are. In addition to the crossing structures, deer guards, escape ramps, pedestrian walk-through gates and the fence end are being monitored.
- Date
- 2018
- Title
- State highway 5 (Mount Evans Road) Summit Lake wetland and hydrology study (Summit Lake Wetland study)
- Abstract
- Due to concerns that the hydrologic regime of the wetland complex in and around Summit Lake Park has been significantly altered by development of State Highway 5 (SH 5), a field study of the hydrology, soils, and vegetation above and below the roadway was initiated in 2018. The objectives of this study are to investigate the natural hydrologic processes and vegetation up-gradient from SH 5, and how they may be impacted in down-gradient areas. A review and synthesis of the road design elements that mitigate the effects of freeze-thaw and permafrost degradation, as well as minimize hydrologic disruption to adjacent wetlands is also included.
- Date
- 2019
- Title
- Dynamic modulus of cold-in-place recycling (CIR) material
- Abstract
- This study investigates the dynamic modulus of Cold-in-Place Recycling (CIR) pavement material and its performance using pavement performance data, field testing, laboratory testing, and Pavement Mechanistic-Empirical Design Guide (PMED) software analysis. Colorado Department of Transportation (CDOT) has 37 projects with over 8 million square yards using CIR materials. Sites from ten projects were selected to monitor the performances, and collect samples for laboratory testing. Field sampling, R-value testing of base/subgrade, and resilient modulus of base/subgrade were conducted. Dynamic moduli testing on the CIR cores were conducted by the CDOT. Considering the field performances of tested CIR pavements, this research recommends CDOT use the data derived from this study to support and implement the continued deployment of this recycling technology.
- Date
- 2018
- Title
- Residual strength of full-depth reclamation
- Abstract
- Cold recycling technologies such as Full-Depth Reclamation (FDR) are sustainable and cost-effective techniques for pavement rehabilitation. Previous research has found current mechanistic-empirical (M-E) default values to be non representative and overly conservative, leading to an underestimation of the true performance capabilities of FDR materials. To address this gap, this research analyzes the performance of 11 FDR sites constructed throughout Colorado and compares their long-term performance with M-E predictions.
- Date
- 2020
- Title
- Western Slope wildlife prioritization study
- Abstract
- The Western Slope Wildlife Prioritization Study (WSWPS) emerged from a commitment to increased collaboration between CDOT and Colorado Parks and Wildlife (CPW) to address wildlife conflicts on roads. The study's objective involved identifying wildlife highway conflict areas where targeted mitigation could have the greatest impact on reducing WVCs. To meet this objective, the mule deer and elk to make cross-highway movements, particularly during migration or within winter range. This report includes a decision-support framework and tools to guide mitigation implementation in the highest advance the outcomes of this research.
- Date
- 2019
- Title
- Migratory Bird Treaty Act compliance, noise and vibration of standard bridge maintenance activity pilot project
- Abstract
- This research report used a pilot project to examine the Migratory Bird Treaty Act (MBTA) and how Colorado Department of Transportation (CDOT) transportation improvement projects may result in noise and vibration levels that could affect migratory birds. The pilot project examined the vibration and noise levels that occurred as a result of standard maintenance activities.
- Date
- 2018
- Title
- Caisson drilling fluid interaction with fine grained bedrock
- Abstract
- This report presents a comprehensive evaluation on the effect of drilling fluid infiltration in claystone bedrock on the axial capacity of drilled caissons. The methodology of this research combines experimental testing and numerical simulations. The results obtained in the experimental phase are used to inform the numerical study.
- Date
- 2020
- Title
- Automated placement and retrieval of traffic cones
- Abstract
- This research report documents the findings of an investigation into automated temporary traffic control device (TTCD) deployment and retrieval technologies. The researchers found that some automated TTCD deployment and retrieval products may reduce one or more types of worker risk while increasing other types of risk. A fully automated product has the potential for the greatest risk reduction overall, but also has a much higher cost than less complex systems.
- Date
- 2017
- Title
- Explicit consideration of safety in the transportation planning process
- Abstract
- The Colorado-specific safety knowledge base, developed and effectively applied in the design process at CDOT, is not yet used to inform the planning process. This report transfers the use of these Colorado-specific, predictive and diagnostic tools to the transportation planning process. It develops a proposed methodology for the Explicit Consideration of Safety in the Transportation Planning Process by focusing on science-based and data-driven project selection, which considers susceptibility to cost-effective correction, rather than simply observed frequency and severity of crashes. This methodology will aid in ranking and prioritizing safety aspects of projects in concert with other attributes, such as mobility, air quality, noise, etc. It effectively translates state-of-the-art safety analysis techniques into an applied, practical methodology that transportation planners and practicing engineers can use.
- Date
- 2017
- Title
- Rock cut perimeter blasting best management practices. Phase 1
- Abstract
- An examination of CDOT design procedures, blasting methods, blast calculations, and aesthetic considerations to specify best management practices for highway rock cut operations for the Colorado Department of Transportation (CDOT) that could be followed when a Contractor or Permittee is proposing to blast. A method was developed to assign quantitative values for aesthetics, called the Percent Aesthetic Enhancement (PAE). By following the PAE practices, the CDOT Engineer-In-Charge can ensure that the Contractor accomplishes the work in a safe manner while preserving scenic, aesthetic, and environmental resources.
- Date
- 2018
- Title
- State Highway 9 wildlife crossings monitoring, year 4 progress report : December 2015 through April 2019
- Abstract
- This research evaluates the effectiveness of the SH 9 Colorado River South Wildlife & Safety Improvement Project, including two wildlife overpasses, and five wildlife underpasses connected with 10.4 miles of wildlife exclusion fencing in Grand County, CO. The project was designed to improve driver safety while allowing for wildlife movement across the road. This study uses motion-activated cameras and WVC crash and carcass data to determine how successful the mitigation measures are. In addition to the crossing structures, deer guards, escape ramps, pedestrian walk-through gates and the fence end are being monitored.
- Date
- 2020