Search results
(1 - 20 of 293)
Pages
- Title
- Internal curing of high performance concrete using lightweight aggregates and other techniques
- Abstract
- Internally cured concrete has been rapidly emerging over the last decade as an effective way to improve the performance of concrete. Internal curing (IC) holds promise for producing concrete with an increased resistance to early-age cracking and enhanced durability. It is a simple and effective way to cure concrete.
- Date
- 2014
- dc.title
- Internal curing of high performance concrete using lightweight aggregates and other techniques
- Title
- Evaluation of seismic testing for quality assurance of lime-stabilized soil
- Abstract
- This study sought to determine the technical feasibility of using seismic techniques to measure the laboratory and field seismic modulus of lime-stabilized soils (LSS), and to compare/correlate test results from bench-top (free-free resonance) seismic testing on LSS cylinders to in-situ (surface seismic) testing performed on field-constructed LSS. In addition, this research sought to develop a pilot specification for quality assurance (QA) of LSS using seismic test methods.
- Date
- 2013
- dc.title
- Evaluation of seismic testing for quality assurance of lime-stabilized soil
- Title
- Full closure strategic analysis
- Abstract
- The full closure strategic analysis was conducted to create a decision process whereby full roadway closures for construction and maintenance activities can be evaluated and approved or denied by CDOT Traffic personnel. The study reviewed current full closure practices in Colorado and throughout the country, gathered stakeholder input, and employed an iterative development process to reach a systematic decision tool that can be applied to judging the merits of full closure scenarios. A number of case studies were created to more fully understand the methodology and adjust the tool to best match real-world scenarios. Project deliverables include a technical report and a series of electronic forms that can be used by CDOT to work through the process.
- Date
- 2014
- dc.title
- Full closure strategic analysis, CDOT full closure strategic analysis
- Title
- Evaluation of the FHWA traffic noise model, TNM, for highway traffic noise prediction in the state of Colorado
- Abstract
- In 2002, CDOT undertook this study in an effort to better understand the complexities of the Federal Highway Administration's new Traffic Noise Model (TNM). The research involved three analysis.
- Date
- 2006
- dc.title
- Evaluation of the FHWA traffic noise model, TNM, for highway traffic noise prediction in the state of Colorado
- Title
- Design of mechanically stabilized earth wall connections and end of walls subjected to seismic loads
- Abstract
- A report that examines the impact that new AASHTO design requirements may have on connection details in mechanically stabilized earth walls.
- Date
- 2014
- dc.title
- Design of mechanically stabilized earth wall connections and end of walls subjected to seismic loads
- Title
- CDOT rapid debris removal research project
- Abstract
- Highway debris represents a traffic safety problem that requires a prompt response from state or local transportation agencies. The most common practice for debris removal currently is for agency personnel to leave their vehicles and remove the debris by hand in the case of large debris (tires, lumber, freight loss, rock fall) or to sweep traveled lanes shoulders, or intersections in the case of crashes, mechanical failure, or embankment erosion. This exposes agency workers to safety risks, especially on high-speed and/or high-volume roadways. Currently, the Colorado Department of Transportation (CDOT) has no widely distributed formal guidelines for safely and effectively removing debris from the roadway.
- Date
- 2014
- dc.title
- CDOT rapid debris removal research project
- Title
- Development of steel design details and selection criteria for innovative and cost-effective steel bridges in Colorado
- Abstract
- In recent years, prestressed concrete bridges have dominated the bridge type selection processes in Colorado. This can be attributed to a lack of steel mills combined with a strong presence of precast fabricators in the region. In addition, a lack of readily available economical and innovative procedures to design and construct steel bridges has hindered the industry in certain areas such as Colorado. During this research it was identified that designing steel girders as simply supported for the non composite dead loads and continuous for composite dead loads and live loads would provide economy. A preliminary girder selection software was created using this design procedure. The software takes user inputted data, such as span length, width, number of girders along with various other design inputs, and displays the lightest wide flange beam size that would support the loads using AASHTO LRFD Design Specifications. Using the girder selection software, design charts and tables were created to outline structural steel weight to span length and number of girders. The design charts will aid the bridge type selection process by giving designers an accurate measurement of minimum steel requirements for numerous one, two, and three span steel bridges.
- Date
- 2008
- dc.title
- , Development of steel design details and selection criteria for cost-effective and and innovative steel bridges in Colorado, , ,
- Title
- Tire/pavement and environmental traffic noise research study
- Date
- 2008
- dc.title
- , , ,
- Title
- Improving the performance of roadside vegetation
- Abstract
- The purpose of this study was to determine the impact of a magnesium chloride-based deicer, a sodium chloride-based deicer, and the major salts contained in these deicers on seed germination and seedling growth and development of fifteen species of grasses and forbs native to Colorado. Seven of the fifteen species performed well at the low and medium concentrations of the salts and solutions; these are plants that can likely germinate in roadside areas.
- Date
- 2011
- dc.title
- , , ,
- Title
- Evaluation of soil resources for sustained vegetative cover of cut-slopes along I-70 near Straight Creek
- Abstract
- A report that evaluates the stability of re-vegetation of high elevation, decomposed, granite cut-slopes by using repeated applications of soil amendments.
- Date
- 2013
- dc.title
- Evaluation of soil resources for sustained vegetative cover of cut-slopes along I-70 near Straight Creek
- Title
- Developing criteria for performance-based concrete specifications
- Abstract
- A report that explains testing of standard mix designs to determine minimum-required performance levels for developing performance-based concrete mix design criteria.
- Date
- 2013
- dc.title
- Developing criteria for performance-based concrete specifications
- Title
- A comparison of freeway and parallel major arterial corridors : a study of safety patterns in the Denver Metropolitan area
- Abstract
- This research project observes and analyzes traffic and accident history on Colorado State Highways and parallel arterial roads within a major southeast section of the Denver Metropolitan Area. The project focuses on the freeway section of C-470 between S. Santa Fe Drive and I-25 and comparisons with I-25 and the corresponding parallel east-west regional arterial corridors.
- Date
- 2015
- dc.title
- A comparison of freeway and parallel major arterial corridors : a study of safety patterns in the Denver Metropolitan area
- Title
- Monitoring wildlife-vehicle collisions : analysis and cost-benefit of escape ramps for deer and elk on U.S. Highway 550
- Abstract
- Wildlife fencing along highways can lower wildlife-vehicle collision rates by excluding animals from the road right-of-way. Still, animals can breach fencing and end up trapped within the fencing along the highway right-of-way, exposing wildlife and motorists to the risk of collision. Wildlife escape ramps are designed to allow animals safe passage out of the right-of-way. Few recommendations exist on effective design of escape ramps and monitoring data are limited.
- Date
- 2015
- dc.title
- Monitoring wildlife-vehicle collisions : analysis and cost-benefit of escape ramps for deer and elk on U.S. Highway 550
- Title
- Optimum use of CDOT French and Hamburg data (French and Hamburg tests)
- Abstract
- The Colorado Department of Transportation (CDOT) has been collecting data from the Hamburg Rutter and the French Rutter for over 20 years. No specifications have been written in that time for either the Hamburg Rutter or the French Rutter. This is largely due to the need for a companion test to be developed so dry asphalt mixes would not be designed specifically for passing the Hamburg Rutter test. This report looks at the state of practice within other states that own similar equipment. Cracking tests that could be run with the Hamburg Rutter are examined from a review of literature to determine if there is a suitable companion test for the Hamburg Rutter that would work to keep asphalt levels in the mix high enough to prevent cracking and fatigue.
- Date
- 2013
- dc.title
- Optimum use of CDOT French and Hamburg data (French and Hamburg tests)
- Title
- Snow route optimization
- Abstract
- Route optimization is a method of creating a set of winter highway treatment routes to meet a range of targets, including service level improvements, resource reallocation and changes to overriding constraints. These routes will allow the operator clear the pavement in a timely and efficient manner, reducing wastage and utilizing resources to their best effect.
- Date
- 2016
- dc.title
- Snow route optimization, Colorado Department of Transportation snow route optimization research report
- Title
- Evaluation of guardrail embedded lighting system in Trinidad, Colorado
- Abstract
- This report provides information on the design considerations of the embedded highway lighting design on Interstate-25 in Trinidad, Colorado, in terms of visibility. The information is based on visibility characterizations of small targets using luminance, illuminance, and contrast calculations as well as participant input on the detectability of small targets.
- Date
- 2014
- dc.title
- Evaluation of guardrail embedded lighting system in Trinidad, Colorado
- Title
- Use of waste tires, crumb rubber, on Colorado highways
- Abstract
- 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.
- Date
- 2014
- dc.title
- Use of waste tires, crumb rubber, on Colorado highways
- Title
- Sustainable stabilization of sulfate-bearing soils with expansive soil-rubber technology
- Abstract
- Pavement construction and maintenance problems due to the presence of sulfates in limestabilized subgrade soils have been widely reported in many transportation projects. In Colorado, problems associated with sulfate-induced distresses have been observed at the Denver International Airport and, more recently, at the U. S. Highway 287 Berthoud By-pass project. It would be desirable if CDOT engineers could count on alternative soil stabilization techniques that are not affected by the potential presence of sulfates.
- Date
- 2013
- dc.title
- Sustainable stabilization of sulfate-bearing soils with expansive soil-rubber technology
- Title
- Assessment and placement of living snow fences to reduce highway maintenance costs and improve safety (living snow fences) study no: 047-10
- Abstract
- Living snow fences (LSF) are designed plantings of trees and/or shrubs and native grasses along highways, roads and ditches that create a vegetative buffer that traps and controls blowing and drifting snow. These strategically placed fences have been shown to be cost effective in reducing highway maintenance associated with blowing and drifting snow conditions.
- Date
- 2015
- dc.title
- Assessment and placement of living snow fences to reduce highway maintenance costs and improve safety (living snow fences) study no: 047-10