Transportation Engineering Commons^™

Contracting Strategies: A Different Approach To Address Long-Term Performance, Maria Calahorra-Jimenez

Mineta Transportation Institute

For cost-efficiency, public safety, and sustainability, improving long-term performance in highway projects is imperative for public administrations. Project delivery and procurement methods provide an opportunity to align design and construction processes with this goal. While previous studies have explored whether project delivery methods impact the long-term performance of highway projects, these studies did not focus on how core elements within project procurement relate to long-term performance. Thus, to fill this gap, this research explores how and to what extent long-term evaluation criteria are considered in design-build best-value procurement of highway projects. To this end, the team conducted content analysis on …

Connected Simulation For Work Zone Safety Application, Vahid Balali

Mineta Transportation Institute

Every year, over 60,000 work zone crashes are reported in the United States (FHWA 2016). Such work zone crashes have resulted in over 4,400 fatal and 200,000 non-fatal injuries in the last 5 years (FHWA 2016, BLS 2014). Apart from the physical and emotional trauma, the annual cost of these injuries exceeds $4 million-representing significant wasted resources. To improve work zone safety, this research developed a system architecture for unveiling high-risk behavioral patterns among highway workers, equipment operators, and drivers within dynamic highway work zones. This research implemented the use of a connected virtual environment, which is an immersive hyper-realistic …

Manual For Asphalt Pavement Repair And Resurfacing Preparation, Dingxin Cheng, Gary Hicks, Roger D. Smith

Mineta Transportation Institute

Timely repairs of pavement defects are essential in protecting an important investment and asset that public agencies have. These repairs may be made as durable “stand-alone” repairs of isolated problems, or as part of preparations for a total resurfacing. This manual provides basic information on the planning, materials and construction aspects of common pavement repairs such as crack sealing, crack filling, and patching, as well as a broader look at other preparations needed for total resurfacing a pavement, whether the resurfacing is a surface treatment or a thin hot mix asphalt (HMA) overlay.

Managing The Curb: Understanding The Impacts Of On-Demand Mobility On Public Transit, Micromobility, And Pedestrians, Susan Shaheen, Elliot Martin, Adam Cohen, Jacquelyn Broader, Richard Davis

Mineta Transportation Institute

In recent years, innovative mobility and shifts in travel and consumption behavior are changing how people access and use the curb. Shared mobility—the shared use of a vehicle, bicycle, scooter, or other mode—coupled with outdoor dining, curbside pick-up, and robotic delivery are creating new needs related to the planning, management, and enforcement of curb access. This study examines curb planning and management from several angles, such as safety, social equity, and multimodal connections. This research employs a multi-method approach to identify the changing needs for curb space management and how to meet these needs through new planning and implementation policies …

Dlr Covid-19 Mobility Review - Coastal Mobility Route (Ph1b): Mobility Update, Sarah Rock Dr, Dave O'Connor, Michael Banim

Reports

The Phase 1b study is a follow up to the evaluation and review of the Phase 1 'Covid-19 Mobility and Public Realm Works' undertaken by Dun Laoghaire- Rathdown County Council in 2020, which included the development of the Coastal Mobility Route (new cycle infrastructure). These works were part of the Council's response to some of the urban and transport planning challenges associated with Covid-19.

This study reports on ongoing monitoring and evaluation of the changing mobility patterns in the region of the Coastal Mobility Route throughout 2021 and 2022, as government and societal responses to the Covid-19 pandemic changed and …

Modelling Monthly Rainfall Of Calabar, Nigeria Using Box-Jenkins (Arima) Method, Francis Ogbozige

Tanzania Journal of Engineering and Technology (TJET)

Rainfall has both positive and negative effects on human activities hence, correct prediction of the period of occurrence is very essential. However, the traditional method of predicting months of heavy rainfall is gradually fading out as irregular rainfall pattern is been experienced in most regions of the world. The rainfall pattern in Calabar city in Southern Nigeria has been reported in past literatures of being irregular. Hence, this research applied the Auto-Regressive Integrated Moving Average (ARIMA) also known as Box-Jenkins method to model the rainfall pattern of Calabar. This was achieved by subjecting 50years monthly rainfall (1971 – 2020) to …

Phased Construction Bridges: Monitoring And Analysis For Traffic-Induced Vibration, Khalid Al-Kady, Christine E. Wittich, Richard L. Wood, George Morcous

Nebraska Department of Transportation: Research Reports

Phased construction is a common technique utilized to allow bridges to remain partially open to traffic throughout the construction process. The segment of the bridge deck that is constructed second cures under the effect of traffic-induced vibration transmitted from the adjacent bridge-deck segment, which is open to traffic. However, subjecting bridge decks to traffic-induced vibration during early-age curing raises concerns about the durability of the decks. The primary goal of this study is to generate a fundamental understanding of the transmission of traffic-induced vibration, the extent of degradation on phased construction bridge decks, and the impact of potential mitigation measures. …

Specialized Safety Training And Tracking For Kytc Construction And Maintenance Personnel, Gabriel Dadi, Ashtarout Ammar, Seth Atkins, Martha Horseman

Kentucky Transportation Center Research Report

High-quality safety training is critical for educating employees in the highway construction and maintenance industry about workplace hazards and giving them tools to remove and/or minimize associated risks. But researchers and state transportation agencies have not committed enough resources to develop safety trainings that address the unique needs of this sector. This report fills in this gap for the Kentucky Transportation Cabinet (KYTC) by cataloguing safety training resources available through other state and federal transportation agencies, documenting trainings available to Cabinet staff, identifying and prioritizing training gaps, and critically evaluating the content, quality, and duration of training resources. A web-based …

Assessing Public Health Benefits Of Replacing Freight Trucks With Cargo Cycles In Last Leg Delivery Trips In Urban Centers, Jennifer C. Hartle, Ossama (Sam) A. Elrahman, Cara Wang, Daniel A. Rodriguez, Yue Ding, Matt Mcgahan

Mineta Transportation Institute

Increased urbanization, population growth, and demand for time-sensitive deliveries means increased freight movement in cities, which contributes to emissions, noise, and safety concerns. One innovative mode gaining widespread attention for urban deliveries is cargo cycles—bicycles adapted for freight delivery. Despite the recognized potential and possible success of transporting at least 25% of freight via cycle, research remains limited. This research investigates the potential of cargo cycle delivery for last mile freight in Oakland, California, with a focus on the West Oakland neighborhood. The data collection included interviews, focus groups, vehicle field observation and counts, and traffic simulation modeling. The traffic …

Influence Of Level 1 And Level 2 Automated Vehicles On Fatal Crashes And Fatal Crash Occurrence, Hardik Gajera, Srinivas S. Pulugurtha, Sonu Mathew

Mineta Transportation Institute

Connected and automated vehicles (CAVs) are expected to improve safety by gradually reducing human decisions while driving. However, there are still questions on their effectiveness as we transition from almost 0% CAVs to 100% CAVs with different levels of vehicle autonomy. This research focuses on synthesizing literature and identifying risk factors influencing fatal crashes involving level 1 and level 2 CAVs in the United States. Fatal crashes involving level 0 vehicles—ones that are not connected and automated—were compared to minimize unobserved heterogeneity and randomness associated with the influencing risk factors. The research team used the fatal crash data for the …

Measuring Accessibility For Pedestrians, Bicyclists, And Transit Riders To Grocery Stores In The Excelsior/Outer Mission Neighborhoods Of San Francisco, Alexandra Lee-Gardner

Master's Theses

Grocery stores are an important amenity in neighborhoods and access to grocery stores is important for health and well-being. While grocery store accessibility is a popular topic of research, studies measuring access for pedestrians, bicyclists, and transit riders are extremely rare. When a new store opened in the Excelsior/Outer Mission districts of San Francisco on a street lacking basic infrastructure for pedestrians, bicyclists, and transit riders, the importance of this study became apparent. The Excelsior/Outer Mission neighborhood has a shocking number of collisions (over 1,100 between 2015 and 2019), elevated levels of walking, biking, and transit ridership, and minimal safe …

Outdoor Laboratory And Testbed For Bridge Health, Richard L. Wood, Mitra Nasimi, Bowen Yang, Christine E. Wittich, Joshua Steelman, Jay Puckett, Daniel Linzell, Jinying Zhu, Mohammad Ebrahim Mohammadi

Nebraska Department of Transportation: Research Reports

Due to the aging problem of bridges and the limited financial resources in the United States, it is necessary to form a deeper understanding of existing, aging bridges in an effort to extend their in-service life. To address this problem, researchers from the University of Nebraska-Lincoln (UNL) and engineers from the Nebraska Department of Transportation (NDOT) identified three, out-of-service bridges (two steel and one concrete) to establish the Nebraska Outdoor Bridge Lab (NOBL). As the first step in NOBL’s development, geometric surveys of the current condition of each bridge were produced using lidar and Structure-from-Motion (SfM). This data contributed to …

Data-Driven Prioritization And Empirical Predictions For Bridge Scour In Nebraska, Richard L. Wood, Awgku Ahmad Hashim B. Awg Bolhasan, Basil Abualshar, Christine E. Wittich, Chung R. Song, Junke Guo, Mohammad Ebrahim Mohammadi, Mitra Nasimi, Yijun Liao

Nebraska Department of Transportation: Research Reports

The effect of scour at the bridge substructure results in an increase in the vulnerability of the overall bridge stability. Previous studies have found that current guidelines are often overly-conservative with respect to scour. This project aims to provide guidance on hydraulic modeling parameters and reasonable scour estimates specific to Nebraska conditions. This will enable engineers to assess bridge sites for scour more precisely for efficient and effective design and countermeasures. Four sites were surveyed for scour changes between the period of December 9, 2020, to April 20, 2021. At these four sites, overland and bathymetry survey data were collected. …

Evaluation Of Polymer Binder Technisoil G5® In Concrete Mixture, Shadi Saadeh, Pritam Katawal

Mineta Transportation Institute

Plastic is everywhere, and with its increasing use in so many everyday materials, the production and demand of plastic has skyrocketed. Unfortunately, this has resulted in the accumulation of a mammoth amount of plastic waste and adverse effects on the environment. To optimize the huge amount of materials required by the pavement industry each year and reuse recycled plastics, the use of reclaimed asphalt pavement (RAP) has been common practice. This research studied the use of a binder completely made from recycled waste plastic named Technisoil G5® and compared it with performance grade PG 70-22 mix containing virgin aggregates and …

Covid-19 Public Transportation Air Circulation And Virus Mitigation Study, Aly Tawfik, Deify Law, Juris Grasis, Joseph Oldham, Moe Salem

Mineta Transportation Institute

COVID-19 may have forever changed our world. Given the limited space and air circulation, potential infections on public transportation could be concerningly high. Accordingly, this study has two objectives: (1) to understand air circulation patterns inside the cabins of buses; and (2) to test the impact of different technologies in mitigating viruses from the air and on surfaces inside bus cabins. For the first objective, different devices, metrics and experiments (including colored smoke; videotaping; anemometers; pressure differentials; particle counts; and 3D numerical simulation models) were utilized and implemented to understand and quantify air circulation inside different buses, with different characteristics, …

Impact Of Dedicated Bus Lanes On Intersection Operations And Travel Time Model Development, Stephen Arhin, Babin Manandhar, Kevin Obike, Melissa Anderson

Mineta Transportation Institute

Over the years, public transit agencies have been trying to improve their operations by continuously evaluating best practices to better serve patrons. Washington Metropolitan Area Transit Authority (WMATA) oversees the transit bus operations in the Washington Metropolitan Area (District of Columbia, some parts of Maryland and Virginia). One practice attempted by WMATA to improve bus travel time and transit reliability has been the implementation of designated bus lanes (DBLs). The District Department of Transportation (DDOT) implemented a bus priority program on selected corridors in the District of Columbia leading to the installation of red-painted DBLs on corridors of H Street, …

Risk-Based Project Development, Steve Waddle, Ying Li, Christopher Van Dyke

Kentucky Transportation Center Research Report

Risk management is integral to highway project development. Managing risk entails identifying uncertainties which could influence project activities, understanding how they can be mitigated or eliminated, and monitoring risk during project development. Many state transportation agencies have introduced methods for identifying risks, determining whether risks are high impact or low impact, and generating response strategies. These methods are often qualitative or semi-quantitative in nature due to the challenge of quantifying the likelihood of a risk and its effects. These approaches are nonetheless valuable for helping designers and project development teams remain mindful of negative risks which could pose significant hurdles. …

Bridge Project Prioritization, Bryan Gibson, Christopher Van Dyke, Sudhir Palle, Ryan Griffith, Doug Kreis

Kentucky Transportation Center Research Report

Kentucky’s 14,000+ bridges are key nodes within the state’s surface transportation network. They facilitate the movement of freight, commercial vehicles, and personal vehicles alike. Historically, the Kentucky Transportation Cabinet (KYTC) has prioritized bridge maintenance projects using sufficiency ratings. These ratings are based on three factors — structural adequacy and safety, design obsolescence, and an asset’s importance within the roadway network. Although useful, sufficiency ratings do not account for factors that should be considered during the prioritization process (e.g., condition factors, risk). To address the shortcomings associated with using sufficiency ratings, KYTC — with the assistance of the Kentucky Transportation Center …

Utilization Of Lidar Technology — When To Use It And Why, Levy Mcintosh, Brad Rister

Kentucky Transportation Center Research Report

Lidar technologies can assist transportation agencies during the design, construction, and maintenance phases of transportation projects. While Lidar has numerous applications, successfully deploying Lidar technologies is only possible if agencies have a solid understanding of their use cases and potential limitations. This report offers guidance the Kentucky Transportation Cabinet (KYTC) can use when making decisions on how to employ Lidar technologies in highway contexts. In addition to reviewing Lidar platforms and comparing Lidar-driven surveying to traditional surveying methods, the report examines challenges related to processing and storing Lidar data and the safety benefits Lidar technologies confer in the field. Brief …

Steel Bridge Coating Inventory For 2022, Christopher Goff, Sudhir Palle

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) has replaced the lead-based coatings on many of its steel bridges over the past 30 years. In the 1980s and 1990s, inorganic zinc primers with vinyl topcoats were the go-to option for coating replacement projects. Since 2000, the typical choice for these projects has been organic zinc primers that are part of a two- or three-coat system. Some of these coatings have localized failures in high-stress areas. KYTC’s current inventory of steel bridges numbers over 1,100 structures. Accounting for expected service lives, to properly maintain protective coatings on these bridges will require the Cabinet to …