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Articles 61 - 90 of 1820
Full-Text Articles in Civil and Environmental Engineering
Best Practices For Recruitment And Retention Of Transportation Professionals, Chris Van Dyke, Bryan Gibson, Sarah Mccormack, Merl Hackbart, Doug Kreis
Best Practices For Recruitment And Retention Of Transportation Professionals, Chris Van Dyke, Bryan Gibson, Sarah Mccormack, Merl Hackbart, Doug Kreis
Kentucky Transportation Center Research Report
Many public sector agencies, including state departments of transportation (DOTs), have long found recruiting and retaining staff a daunting challenge. Lured by the promise of higher salaries in the private sector, many people are reluctant to sacrifice their long-term earnings potential to pursue public service. And with the quality of fringe benefits (e.g., retirement plans, health insurance) offered by public agencies having declined gradually, it is even more difficult to persuade prospective employees to accept a lower salary. Many studies over the past 15—20 years have looked at methods for solving the problem of recruitment and retention within the context …
Pilot Study On Improving Crash Data Accuracy In Kentucky Through University Collaboration, Michael A. Fields, Eric Green, Robert Kluger, Xu Zhang, Kirolos Haleem
Pilot Study On Improving Crash Data Accuracy In Kentucky Through University Collaboration, Michael A. Fields, Eric Green, Robert Kluger, Xu Zhang, Kirolos Haleem
Kentucky Transportation Center Research Report
Without high-quality crash data and robust interpretive/analytical tools to analyze these data, transportation agencies will struggle to develop evidence-based strategies for improving road safety. Crash narratives are one element of crash reports that pose especially acute interpretive challenges. These narratives supplement coded data and give an account of incidents authored by responding law enforcement officers. Despite their value, conducting manual reviews of the 150,000+ crash reports and narratives issued in Kentucky each year is not feasible. To address this challenge, reviewers examined approximately 8,000 crash narratives from calendar year 2020 using a proprietary web-based quality control tool to identify discrepancies …
Advancing Universal Id Through Demonstration Of Enabling Technologies, Joseph Crabtree, Andrew Martin, Jeeyen Koo, Brian Beaven
Advancing Universal Id Through Demonstration Of Enabling Technologies, Joseph Crabtree, Andrew Martin, Jeeyen Koo, Brian Beaven
Kentucky Transportation Center Research Report
The purpose of this project was to install, demonstrate, and evaluate two candidate technologies that could be used to achieve “Universal ID” (i.e., having a unique, electronically readable identifier on every commercial motor vehicle in the United States). The two technologies selected for this demonstration represent (1) a potential low-cost near-term solution (simple RFID tags and roadside readers) and (2) a potential future solution that leverages technology that is anticipated to be installed on all future vehicles to support a variety of connected-vehicle (CV) applications. For this demonstration project, both types of roadside reader technology were installed at three existing …
Safety Evaluation Of 2+1 Roadway Design, Kenneth R. Agent, Jeff Jasper
Safety Evaluation Of 2+1 Roadway Design, Kenneth R. Agent, Jeff Jasper
Kentucky Transportation Center Research Report
An assessment and analysis of the safety of 2+1 roads introduced in 2013 and later.
Kytc Department Of Aviation Aircraft Maintenance Technician (Amt) Program Optimization, Bethany Paris, P. Gayle Marks, Bryan Gibson
Kytc Department Of Aviation Aircraft Maintenance Technician (Amt) Program Optimization, Bethany Paris, P. Gayle Marks, Bryan Gibson
Kentucky Transportation Center Research Report
The aviation industry is a linchpin of Kentucky’s economy. Major firms such as UPS, Amazon, and DHL have major hubs at Louisville Muhammad Ali International Airport (SDF) and Cincinnati/Northern Kentucky International Airport (CVG). As of December 2022, 4,570 aircraft mechanics and service technicians (AMTs) were employed in the state. Demand in this sector is poised to grow. As such, it is critical to understand what resources Kentucky has available to train the next generation of professionals and the number of people the aviation industry is likely to employ statewide over the next decade. Kentucky and the surrounding states are home …
2023 Final Report For Databases In The 2022 Traffic Records Improvement Plan: Facilitating The Development Of Projects To Attain The Goals In The Implementation Plan For The 2022-26 Traffic Records Strategic Plan, Lenahan O'Connell, Samantha Wright, Reginald Souleyrette
2023 Final Report For Databases In The 2022 Traffic Records Improvement Plan: Facilitating The Development Of Projects To Attain The Goals In The Implementation Plan For The 2022-26 Traffic Records Strategic Plan, Lenahan O'Connell, Samantha Wright, Reginald Souleyrette
Kentucky Transportation Center Research Report
During fiscal year 2023, with financial support (Grant #M3Da-2022-04) from the Kentucky Office of Highway Safety, the Kentucky Transportation Center (KTC)-continued its work with traffic database officials to facilitate successful attainment of the remaining goals from the 2017-21 Traffic Records Strategic Plan (TRSP), which goals are in the 2022-26 TRSP Transportation Records Improvement Plan (TRIP). For most databases, some new goals were developed; this required further refinement of some projects or strategies to improve database performance. Projects to complete the goals in the TRIP were continued and some completed for the following databases: CRASH, Citation/Adjudication, Injury Surveillance (KIPRC and EMS), …
Kentucky Traffic Collision Facts 2022 Report, Paul Ross, Eric Green, Christopher Blackden, Kenneth R. Agent, Christopher Van Dyke
Kentucky Traffic Collision Facts 2022 Report, Paul Ross, Eric Green, Christopher Blackden, Kenneth R. Agent, Christopher Van Dyke
Kentucky Transportation Center Research Report
Kentucky’s Traffic Collision Facts is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statute 189.635: “Every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize data on traffic collisions to improve the Commonwealth’s traffic safety program. Unless otherwise noted, data in this publication are for public roads only. Data contained in this report are based solely …
Analysis Of Traffic Crash Data In Kentucky 2018-2022, Paul Ross, Eric Green, Christopher Blackden, Christopher Van Dyke
Analysis Of Traffic Crash Data In Kentucky 2018-2022, Paul Ross, Eric Green, Christopher Blackden, Christopher Van Dyke
Kentucky Transportation Center Research Report
This report documents analysis of traffic crash data in Kentucky. A primary objective of this study was to determine average crash statistics for Kentucky highways. Where used, rates were calculated for various highway types and for counties and cities. Difference criteria were used for exposure. Average and critical numbers, SPFs, and crash rates were calculated for various highway types in rural and urban areas. These metrics rely on crashes identified on highways where Annual Average Daily Traffic (AADT) volumes were available. Data in this report may be used to help identify problem areas. The other primary objective of this study …
2023 Safety Belt Usage Survey In Kentucky, Erin Lammers-Staats, Derek S. Young, Kenneth R. Agent, Aidan Elias
2023 Safety Belt Usage Survey In Kentucky, Erin Lammers-Staats, Derek S. Young, Kenneth R. Agent, Aidan Elias
Kentucky Transportation Center Research Report
Data and results of a statewide observational survey used to establish the statewide usage rate for safety belts in Kentucky.
Evaluation Of Durable Pavement Striping, William Staats, Erin Lammers-Staats
Evaluation Of Durable Pavement Striping, William Staats, Erin Lammers-Staats
Kentucky Transportation Center Research Report
Roadway pavement markings, colloquially referred to as “striping”, can be made of various combinations of paint and reflective beads. In the interest of aligning Kentucky with the state-of-the-art durable pavement marking practices of other states, the Kentucky Transportation Cabinet (KYTC) developed a research study aimed at improving pavement marking specifications and practices. This study reviewed current practices, identified potential improvements, and performed a systematic evaluation in a controlled environment on both asphalt and concrete roads. The state evaluated high-build waterborne paint, extruded and spray thermoplastic, polyurea, and preformed plastic tape, as well as several bead packages including M247, Missouri blend, …
Inspection Training Course On Bridge Preventive Maintenance Activities, Danny Wells, Sudhir Palle
Inspection Training Course On Bridge Preventive Maintenance Activities, Danny Wells, Sudhir Palle
Kentucky Transportation Center Research Report
Despite over 30 percent of bridges in the United States having exceeded their 50-year design lives, most state departments of transportation (DOTs) lack the funding needed to replace bridges on a large scale. In response, agencies have increasingly turned to bridge preventive maintenance activities to prolong bridge service lives. These activities provide a safe and cost-effective way to slow the rate at which structures deteriorate, mitigate the effects of aging, and improve bridge functional condition. The Kentucky Transportation Cabinet (KYTC) has become increasingly reliant on preventive maintenance to preserve and extend the service lives of its steel and concrete bridges. …
Friction And Texture Equipment Correlation Study, David Hacker, Kean H. Ashurst Jr., Clark Graves
Friction And Texture Equipment Correlation Study, David Hacker, Kean H. Ashurst Jr., Clark Graves
Kentucky Transportation Center Research Report
The Kentucky Transportation Cabinet’s (KYTC) foremost goal is building and maintaining a safe road network. To accomplish this goal, KYTC needs reliable pavement friction and macrotexture data, both of which influence road performance and safety. KYTC currently measures fiction using a lock-wheel skid tester (AASHTO T 242), however, the agency has not been able to collect data at the network level due to equipment and personnel limitations. In 2020 the Cabinet commissioned a study to collect friction and macrotexture data. Investigators used a sideway-force coefficient routine investigation machine (SCRIM) (AASHTO TP 143) to measure friction. To understand the performance of …
Combined Behavioral And Engineering Approach To Preventing Highway Fatalities, Benjamin Blandford, Reginald Souleyrette, Caitlin N. Pope, Tony Fields, Erin Lammers-Staats
Combined Behavioral And Engineering Approach To Preventing Highway Fatalities, Benjamin Blandford, Reginald Souleyrette, Caitlin N. Pope, Tony Fields, Erin Lammers-Staats
Kentucky Transportation Center Research Report
Traditional, single-discipline highway safety approaches can be augmented through multidisciplinary approaches that consider both engineering and behavioral interventions (e.g., education, enforcement, public outreach campaigns). Leveraging a systems-based conceptual framework of roadway safety, multiple forms of statistical and geospatial analysis, and SPF modeling and network screening, this report proposes and demonstrates methods for unpacking the influence of behavioral-related factors on crash occurrences and outcomes. The primary focus is on behaviors targeted in the Strategic Highway Safety Plan — aggressive driving, distracted driving, impaired driving, and driving without proper restraint (i.e., seatbelts). Based on application of these methods, the report highlights areas …
Evaluating The Use Of A Near-Miss Reporting Program To Enhance Employee Safety Performance, Gabriel Dadi, Farshid Taherpour, Seth Atkins, Ashtarout Ammar, Jon Wilcoxson
Evaluating The Use Of A Near-Miss Reporting Program To Enhance Employee Safety Performance, Gabriel Dadi, Farshid Taherpour, Seth Atkins, Ashtarout Ammar, Jon Wilcoxson
Kentucky Transportation Center Research Report
Using safety incidents and crashes to improve safety performance is an outdated and reactive practice in safety and health programs. One component of a modern approach to safety is a near-miss reporting program. This type of program tracks close calls or near misses that do not result in an incident or crash, but which often can be an early indicator that one may happen. While most construction companies have implemented some methods for reporting near-miss events, many agencies, such as the Kentucky Transportation Cabinet (KYTC), struggle getting employees to report near misses. To fill this gap, potential factors that result …
Innovative Methods To Strengthen Internal Kytc Communications, P. Gayle Marks, Jeff Jasper
Innovative Methods To Strengthen Internal Kytc Communications, P. Gayle Marks, Jeff Jasper
Kentucky Transportation Center Research Report
Communication is the linchpin of every organization. Poor communication leads to inefficiencies, frustration among staff, and employee disaffection and disengagement. Although some state transportation agencies have adopted comprehensive strategic plans for internal communications, many have taken a more piecemeal approach, with some Offices and units (e.g., incident management) developing their own plans that apply only to their operations. The latter approach is less than ideal because establishing a comprehensive communications plan provides an organizing framework for all communications within an organization and is critical for uniting staff around a shared sense of purpose and equipping them with the tools they …
Facilitated Identification Of Kytc Performance Measures, Candice Wallace, Jon Wilcoxson
Facilitated Identification Of Kytc Performance Measures, Candice Wallace, Jon Wilcoxson
Kentucky Transportation Center Research Report
Federal and state government agencies are embracing performance management as a means to (1) justify the use of tax dollars and (2) monitor and report program accomplishments. The Kentucky Transportation Cabinet’s (KYTC) efforts to fold Transportation Performance Management (TPM) into its business processes and workplace culture required training that would educate personnel about TPM’s benefits, objectives, and activities. After reviewing training resources on performance management from FHWA, NHI, AASHTO, and state DOTs, Cabinet leadership concluded that their emphasis on federal requirements was not exactly what KYTC was looking for in a training program. Instead, KYTC wanted a training program that …
Transportation Infrastructure Needs In The Central Appalachian Basin To Support Core-Cm, Bryan Gibson, Robin Baskette, Doug Kreis
Transportation Infrastructure Needs In The Central Appalachian Basin To Support Core-Cm, Bryan Gibson, Robin Baskette, Doug Kreis
Kentucky Transportation Center Research Report
With demand for coal from the Central Appalachian Basin waning, coalitions and organizations throughout the region have sought to diversify the region’s economy. However, the potential exists to use coal and coal-based resources to produce new and innovative products and kick start economic growth in the basin. This includes carbon ore, rare earth and critical minerals (CORE-CM), other minerals, and waste streams. If the region is to take advantage of these economic growth opportunities, transportation infrastructure must be developed and maintained in a sound condition. Reliable roads, highways, and bridges provide rural areas with access to capital, labor, and markets …
Merging Multiple Existing Geotechnical Databases, Charlie Sun, Brad Rister, Eileen Grady
Merging Multiple Existing Geotechnical Databases, Charlie Sun, Brad Rister, Eileen Grady
Kentucky Transportation Center Research Report
This report discusses a project undertaken by Kentucky Transportation Center (KTC) researchers to create a comprehensive geotechnical database for highway planning, design, maintenance, and repair. The project consolidated multiple geotechnical data sources into a unified database accessible to Kentucky Transportation Cabinet (KYTC) staff, enabling informed decision making and improving project outcomes. Databases were merged with great attention to detail, ensuring data integrity and coherence. A geotechnical data collector app developed as part of the project supports convenient and efficient data collection in the field, even when phones or tablets lack network connectivity. A rockfall rating app and landslide hazard rating …
Fiscal Year 2021 Fhwa-536 Report For The Kentucky Transportation Cabinet, Doug Kreis, Candice Wallace, Bryan Gibson, Sarah Mccormack
Fiscal Year 2021 Fhwa-536 Report For The Kentucky Transportation Cabinet, Doug Kreis, Candice Wallace, Bryan Gibson, Sarah Mccormack
Kentucky Transportation Center Research Report
No abstract provided.
Incorporating Variability In Kytc Planning And Project Development, Reginald Souleyrette, Teng Wang, Riana Tanzen, Arnold Stromberg
Incorporating Variability In Kytc Planning And Project Development, Reginald Souleyrette, Teng Wang, Riana Tanzen, Arnold Stromberg
Kentucky Transportation Center Research Report
Transportation planning and design decisions are typically made using point estimates of traffic and safety measures. This report addresses the uncertainty of data used to make these decisions. It focuses on two data elements — project safety ratings and volume estimates from traffic counts. For safety ratings, the Kentucky Transportation Cabinet’s Strategic Highway Investment Formula for Tomorrow (SHIFT) crash history score is used as a case study. Confidence intervals are developed for the Cabinet’s new safety metric, which incorporates estimates of future crashes by severity as well as excess expected crashes above safety goals. For traffic counts, the report develops …
Incorporating Crash Severity And Continuous Improvement Of Shift, Reginald Souleyrette, Riana Tanzen, Teng Wang
Incorporating Crash Severity And Continuous Improvement Of Shift, Reginald Souleyrette, Riana Tanzen, Teng Wang
Kentucky Transportation Center Research Report
The Strategic Highway Investment Formula for Tomorrow (SHIFT) is the Kentucky Transportation Cabinet's data-informed approach for comparing capital improvement projects and prioritizing limited transportation funds. SHIFT 2022 incorporates advancements in methods and flexibility. This project revises the SHIFT crash data safety metric. The crash data safety metric from the previous version of SHIFT was excess expected crashes (EECs). It is computed using the total number of crashes of all severities. Locations with a higher proportion of severe (fatal and injury) crashes received the same weight as locations with an equal number of property damage only crashes. This project redefines the …
Existing Transportation Infrastructure In The Central Appalachian Basin To Support Core-Cm, Bryan Gibson, Robin Baskette, Doug Kreis
Existing Transportation Infrastructure In The Central Appalachian Basin To Support Core-Cm, Bryan Gibson, Robin Baskette, Doug Kreis
Kentucky Transportation Center Research Report
Stretching from Tennessee northeastward through southwestern Pennsylvania, the Central Appalachian Basin’s economic fortunes have long depended on coal production. However, as the U.S. has increasingly turned toward new forms of energy to generate electricity, the region’s economy has faced inexorable headwinds. Yet, what is clear is that the extractive industries are likely to play a key role in shaping the basin’s economy in the years to come. Taking this assumption as a starting point, this paper discusses how well current transportation infrastructure can support expanded us of the basin’s carbon ore, rare earth, and critical minerals (CORE-CM), other minerals, and …
Graduated Driver Licensing Program, Jeeyen Koo, Andrew Martin, Jennifer Walton
Graduated Driver Licensing Program, Jeeyen Koo, Andrew Martin, Jennifer Walton
Kentucky Transportation Center Research Report
To address challenges related to teen driver safety, Kentucky adopted a simple graduated driver licensing (GDL) program in 1996 and further expanded it in 2006 by adding an intermediate licensing phase, requirements for supervised practice driving, and instituting restrictions on passenger age. Despite GDL programs having been adopted throughout the US, young drivers (ages 16 – 20) continue to be overrepresented in fatal crashes. In 2019, despite this segment making up roughly 5.3 percent of licensed drivers it accounted for 11.5 percent of fatal vehicle crashes (Kentucky recorded 732 crash fatalities, of which 73 involved young drivers). Although teen driver …
2+1 Roadway Design Guidance Update, Jeff Jasper, Jeff Wolfe, Robin Baskette, Paul Ross, Chris Van Dyke
2+1 Roadway Design Guidance Update, Jeff Jasper, Jeff Wolfe, Robin Baskette, Paul Ross, Chris Van Dyke
Kentucky Transportation Center Research Report
The frequency and severity of crashes on rural two-lane roadways have increased in the US relative to other road types. This trend can be explained by the growing number of vehicles, higher speeds, narrow shoulders, and vehicle mixes. One solution for improving traffic flow and safety outcomes on rural two-lane roadways is to adopt a 2+1 design, which confers the benefits of four-lane highways but at a lower cost. Transportation agencies throughout Europe — and increasingly the US — have seen good results from 2+1 layouts. Crash data from Sweden, Germany, Finland, and Denmark reveal better safety outcomes following the …
Pedestrian And Bicycle Improvement Scoring Method For Shift–2024, Nikiforos Stamatiadis, Daria Korostina, Teng Wang, Reginald Souleyrette
Pedestrian And Bicycle Improvement Scoring Method For Shift–2024, Nikiforos Stamatiadis, Daria Korostina, Teng Wang, Reginald Souleyrette
Kentucky Transportation Center Research Report
State transportation agencies have limited funding to deliver multimodal transportation programs that address the needs of all users. To allocate project funding in an impartial and objective manner, many agencies have adopted data-driven scoring systems that are used to evaluate the merits of proposed capital improvement projects. The Kentucky Transportation Cabinet introduced the Strategic Highway Investment Formula for Tomorrow (SHIFT) for this purpose. Until now SHIFT, has evaluated projects based five core variables — congestion, safety, benefit-cost ratio, asset management, economic growth. To address local needs, SHIFT has also allocated points that Area Development Districts, metropolitan planning organizations, and Cabinet …
Spf-R Online User Guide, Eric Green, Paul Ross, Christopher Blackden, William Staats, Reginald Souleyrette
Spf-R Online User Guide, Eric Green, Paul Ross, Christopher Blackden, William Staats, Reginald Souleyrette
Kentucky Transportation Center Research Report
SPF-R Online greatly improves and simplifies the SPF development process. Building on the original SPF-R script, the online tool eliminates many of the technical barriers associated with the original process, allowing for a much larger audience to take advantage of SPF-R’s capabilities. Like the original SPF-R script, SPF-R Online lets users quickly explore the effect of roadway network heterogeneity on SPF development, compare CURE plots , and compare goodness-of-fit measures to decide which SPF is most appropriate for a given dataset.
Best Practices For Highway Project Scoping, Jeff Jasper, Samantha Wright, Jon Wilcoxson, Robin Baskette, Christopher Van Dyke
Best Practices For Highway Project Scoping, Jeff Jasper, Samantha Wright, Jon Wilcoxson, Robin Baskette, Christopher Van Dyke
Kentucky Transportation Center Research Report
One of the Kentucky Transportation Cabinet’s (KYTC) foremost priorities in fulfilling its mission is to deliver successful projects — quality solutions that meet the defined scope and are delivered on time and within the budget specified in the Highway Plan. When a project scope is not clearly defined or uncertain, revisions may take place after the project is already underway, leading to delays or overpromising what can be delivered. Ideally, a reliable, decisive project scope is defined in the early phases of the highway project development process. The scope should include a project definition that clearly communicates the project scope’s …
Rapid Pothole Repair In Concrete Bridge Decks, Abheetha Peiris, Issam Harik
Rapid Pothole Repair In Concrete Bridge Decks, Abheetha Peiris, Issam Harik
Kentucky Transportation Center Research Report
Using traditional methods to repair potholes in reinforced concrete (RC) bridge decks is time-consuming and requires significant manpower and equipment. However, commercially available epoxies and similar materials provide a repair option that does not require saw cutting the deck around the pothole, concrete removal, and replacement. Researchers laboratory tested three epoxies to identify which is best for pothole repairs. Based on assessments of substrate penetration times and set times for epoxy and epoxy mortar, as well as compressive strength gain over time for epoxy mortar, researchers selected Sikadur 52 for static and dynamic bending tests using small-scale beams with simulated …
Kentucky Traffic Collision Facts 2021 Report, Paul Ross, Eric Green, Christopher Blackden, Michael Fields, Kenneth Agent, Christopher Van Dyke, Ed Harding
Kentucky Traffic Collision Facts 2021 Report, Paul Ross, Eric Green, Christopher Blackden, Michael Fields, Kenneth Agent, Christopher Van Dyke, Ed Harding
Kentucky Transportation Center Research Report
Each year the Kentucky Transportation Center publishes the Traffic Collision Facts report in collaboration with the Commonwealth of Kentucky, Kentucky State Police, and Kentucky Transportation Cabinet. This is the fiscal year 2022 report, which covers collisions reported during calendar year 2021. For the year, 734 fatal crashes, 20,117 nonfatal crashes, and 88,440 property damage only crashes occurred on the state’s roadways. Overall, 109,291 crashes were reported in calendar year 2021, a 8.4 percent increase over calendar year 2020.
Analysis Of Traffic Crash Data In Kentucky 2017-2021, Paul Ross, Eric Green, Christopher Blackden, Christopehr Van Dyke, Michael Fields, Riana Tanzen
Analysis Of Traffic Crash Data In Kentucky 2017-2021, Paul Ross, Eric Green, Christopher Blackden, Christopehr Van Dyke, Michael Fields, Riana Tanzen
Kentucky Transportation Center Research Report
Each year the Kentucky Transportation Center publishes Analysis of Traffic Crash Data in Kentucky, a report that reviews state-level crash data from the previous five years. This report summarizes crash data for 2017 through 2021. In addition to presenting a review of crash data, the report also contains safety performance functions (SPFs) for nine roadway types. Because SPFs were derived using 2017-2021 data, the models predict crashes for a five-year period. Users must adjust the model by adding a coefficient of 1/5 to models to avoid overestimating crashes by a factor of five.