Search results
(1 - 20 of 309)
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
- 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
- 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
- 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
- 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
- Statewide economic benefits of transportation investments
- Date
- 2007
- dc.title
- , , ,
- Title
- Tire/pavement and environmental traffic noise research study
- Date
- 2008
- dc.title
- , , ,
- Title
- Factors impacting the health of roadside vegetation
- Abstract
- Roadside vegetation is exposed to a variety of biotic and abiotic stresses that can impact plant health. Drought, pollution, disease, insects, lack of nutrients, and roadbed management practices may potentially act alone or synergistically to adversely affect plants in proximity to the roadside. To date, little published research documents the impacts of certain deicers on vegetation in relationship to other potential stresses. This study provides an ecological impact assessment of factors affecting the health of roadside vegetation in the state of Colorado including potential biotic and abiotic plant stressors and deicer applications.
- Date
- 2007
- dc.title
- , , ,
- 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
- 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
- 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
- Performance of thin bonded epoxy overlays on asphalt and concrete bridge deck surfaces
- Abstract
- This study is the evaluation of two thin bonded epoxy overlays. These two products were compared on the basis of physical properties, including mean texture depth, surface friction, bond strength, ability to stop chloride intrusion, and anti-icing properties, as well as traffic safety and cost. Both overlays worked as intended when they were initially applied on the bridge decks. Mean texture depth and friction testing have shown that they both provide a durable wearing surface with good traction.
- Date
- 2014
- dc.title
- Performance of thin bonded epoxy overlays on asphalt and concrete bridge deck surfaces
- Title
- Benefit-cost analysis of CDOT fixed automated spray technology (FAST) systems
- Abstract
- The study found that FAST systems have demonstrated the potential to reduce the number of crashes and reduce the cost of winter maintenance activities, if sited at appropriate locations (e.g., high-traffic-volume ice-prone ramps). However, improved installation techniques and involvement of maintenance crews during FAST installation are necessary to further increase the cost-effectiveness of a FAST system deployment. Extra effort will be made in sharing the information gained from this research study by focusing on CDOT personnel involved in planning, design, construction, operation and maintenance of FAST systems.
- Date
- 2014
- dc.title
- Benefit-cost analysis of CDOT fixed automated spray technology (FAST) systems
- 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