Safety Behavior and Gender Split Differences in Micromobility: A Q&A Interview with Researcher


Q. How was your research funded?    

This work was supported by the National Science Foundation under a grant called “Making Micromobility Smarter and Safer”. The lead on this is Dr. Clint Andrews at Rutgers University and there are several other principal investigators. My study acts as a part of this multi-year research.  

Q.  Can you share a brief overview of your findings? Are the results surprising or unique compared to past research?    

We are one of the only studies comparing the safety behavior of cyclists and e-scooter users across genders. Without considering gender, we found that one-third of cyclists wore a helmet. We also found in our observations that e-scooter users did not wear a helmet. It speaks to how important it is to have safe micromobility infrastructure, especially knowing that people are unlikely to wear a helmet. In the U.S., even if you give everyone a helmet, they’re probably not going to wear it. That’s just how it is. Keeping people safe in other ways is paramount.  

We also found that a greater proportion of women were using e-scooters than bicycles. This is important because cycling has long been a male-dominated mode of transportation, for a variety of reasons. That is true across the world. There are studies that suggest women are less likely to cycle to work because of clothing like wearing a skirt or dress or heels, or fears of sweating. E-scooters remove that hurdle since they are not as prohibitive in terms of clothing and require less physical exertion. So, the vehicle type itself may make a difference. Moreover, women place more importance on bike lane infrastructure than men.  If we are seeing that e-scooters are the preferred mode for females, perhaps e-scooters can help narrow the gender gap in micromobility. 

Q.  Can you talk a little bit about the methods used for this study? How are these methods different from past research? Why did you choose to use traffic cameras for your observations?

This work was done using manual observations, a common method in micromobility studies. Previous research had used observations collected in the field. Instead of having observers in the field, we observed traffic camera footage at one intersection. Because we were observing gender and race as well as group behavior, the footage was useful as it allowed us to pause when needed. It was also less resource intensive than having a person stand in the field since no travel expenses were associated with the analysis.  

Q.  What challenges have you found in working with and interpreting traffic camera footage? With the improvement of AI technologies, do you think there will be an opportunity to automate this process in the future?  Are there any limitations you expect from this type of innovation?  

It is very time consuming and tedious to analyze this much camera footage. We analyzed 35 hours of footage. I would love to have analyzed more, but you have to draw the line somewhere depending on the resources available for the research or project study. Most of the time, we fast forwarded until a micromobility user was detected, but it still requires undivided attention. There is a possibility with current technology to incorporate AI technologies: to use computer vision to detect humans, which then can be manually viewed by a human to assess micromobility mode, gender, and helmet use. This would likely reduce the manual labor… It would be interesting to compare the computer vision model to the work I have done… Nonetheless, computer vision does not differentiate properly between pedestrians and e-scooter users, so it is prone to misidentification, which would lengthen the time taken to observe manually.  

At this point, computer vision cannot detect gender, helmet use, and group riding properly from traffic camera footage. More high-resolution images would be needed to differentiate gender and helmet use (like unobstructed face images) and group riding requires context clues like making eye contact, waiting for one another, etc. AI has the potential, but it is not there yet.  As time consuming as it is, I am confident that we detected every person, which is why we chose to observe the footage ourselves.  

Q.  What are the limitations of this study? Do you have plans for future research to address these?  How would you like to expand your research on this topic?   

The main limitation is the geographical scope of this research; it’s a lot of work for one city. We only analyzed the behavior of micromobility in one location, Asbury Park. It isn’t clear how much the results will translate from one location to another. Mode of transportation and behavioral use depends on many different factors that vary from location to location. There is evidence that the gender gap is smaller for e-scooter users in Brisbane, Australia, but not to the extent observed in Asbury Park. Same goes with helmet use. A larger scale study would be useful. Other limitations include the types of micromobility modes: we only observed shared e-scooters and privately owned bicycles in Asbury Park. So, we’re comparing two different vehicles and two different share types to one another. When analyzing the data, we must consider both of these factors. For example, are behaviors attributed solely to the vehicle or to the share type? Probably both. When you’re looking at the gender gap, is it because it’s an e-scooter or is it because it’s shared that there is a narrower gender gap?  

 An analysis comparing shared and privately owned e-scooters with shared and privately owned bicycles would be great. Differentiating between e-bikes and bicycles would be great too, although the resolution of traffic camera footage makes it very hard to differentiate between the two. Even with an observer onsite, it would be hard to detect, so you would need a survey, but this could alter behavior. In Asbury Park, a lot of people have privately owned e-scooters now, so we could do another study in 1.5-2 years and get additional insights in the same location.  

E-bikes are a growing mode of transportation, but even with traffic camera footage, it is very hard to tell an e-bike apart from a bicycle, so maybe in that case you would need somebody on site actually observing. You’re losing the ability to pause footage, but it might be more useful if you’re looking at e-bikes. Race and age were also very difficult to observe from the footage. It could be easier if someone was in person to observe in addition to the traffic camera footage. Even then, without asking directly the age and race/ethnicity of the user, there will be bias. There are a lot of different things to consider; it really depends on what the question is.  

Q.  How would you like this research to inform transportation agencies and practitioners in New Jersey and elsewhere?    

There are several key points. Users of shared e-scooters and privately owned bicycles are different and behave differently. E-scooter users are more likely to take risks like not wearing a helmet or riding on the road. Planners must ensure that the infrastructure keeps them safe. That is, implementing dedicated protected bike lanes that are connected to a greater network and adding traffic calming measures to slow the speeds of motor-vehicles like raised crosswalks or narrower traffic lanes.

Understanding the reasons behind lane use is important as well, as there are concerns for pedestrian safety. Our research observed that lane use was different; for example, 7 percent of male cyclists rode on the sidewalk, compared to 28 percent of female e-scooter users.

Additionally, having a shared e-scooter system in a city can increase female participation in micromobility use. It is a more gender equitable mode than bicycles. Other agencies might want to implement an e-scooter share program in their town.  

Q.  Your research shows that women were more likely than men to ride on the sidewalk while using an e-scooter or bike. Given that this strategy is illegal in most parts of the country, how can planners, engineers and policymakers use this information to increase feelings of safety for female micromobility users?     

This is really interesting. From my research, there is not a lot that I could say. Implicitly, one of the reasons for someone to ride on the sidewalk instead of the road is that they feel safer on the sidewalk. There is a need to ensure that micromobility users feel just as safe on the road–that is, implement a dedicated and protected bike lane, and provide a clear separation from motor-vehicles.

From our work, we know that there are other more complex factors at play: our research had clear results for road lane use with the implementation of the bike lane, but less clear ones for sidewalk use: sidewalk use was not significantly reduced by the presence of a pop-up bike lane. To encourage safe road use, ensuring a complete network would be a start. The pop-up bike lane was not connected to another bike lane going downtown, for instance. If you’re already coming downtown on the sidewalk, you might be more likely to stay there given the existing curb that would need to be crossed to go from the sidewalk to the pop-up bike lane.  

Q.  NJDOT is sponsoring a program to ensure the implementation of the Statewide Bicycle and Pedestrian Master Plan. In what ways could this master plan or a future one align with the findings in your study?  

The results of this study reinforce that implementing a bike lane provides a layer of safety for micromobility users. Nearly all the increase in bike lane usage came from a reduction in traffic lane usage, not in sidewalk usage. There is so much research out there that shows that bike lanes save lives; in the case of a crash, someone in a bike lane is less likely to be injured. Ensuring that plans accommodate both bicycles and e-vehicles–like e-bikes and e-scooters–is also paramount.  

Q.  The Biden Administration has set a goal to achieve a net zero emissions economy by 2050. How might a shift toward micromobility help the nation reach its climate and carbon emission goals?    

Bicycles are zero emission vehicles. E-bikes and e-scooters produce few emissions, especially privately owned ones since they don’t require rebalancing. Rebalancing shared vehicles requires a car or van and those gasoline emissions are absorbed by those shared e-scooters. Having an e-vehicle do that for rebalancing helps to reduce those emissions. Bicycle-friendly infrastructure, which reduces motor-vehicle infrastructure such as the number of traffic lanes, or parking, can also reduce motor-vehicle use and induce more environmentally friendly travel.   

Q.  How could a focus on reaching these climate goals impact the way that planners and engineers design streets?    


Resources

Blickstein, S.G., Brown, C.T., & Yang, S. (2019). “E-Scooter Programs Current State of Practice in US Cities.” Retrieved from https://njbikeped.org/e-scooter-programs-current-state-of-practice-in-us-cities-2019/

Marshall, H. (2023). “How do Female Cyclists Perceive Different Cycling Environments? – A Photo-elicitation study in Stockholm, Sweden.” Retrieved from https://gupea.ub.gu.se/handle/2077/78209

NJDOT Technology Transfer. (2020). “Tech Talk! Launching Micromobility in NJ and Beyond.” Retrieved from https://www.njdottechtransfer.net/2020/02/25/launching-micromobility-in-nj-and-beyond/

NJDOT Technology Transfer. (2021). “How Automated Video Analytics Can Make NJ’s Transportation Network Safer and More Efficient.” Retrieved from https://www.njdottechtransfer.net/2021/11/08/automated-video-analytics/

NJDOT Technology Transfer.(2022). “Research Spotlight: Exploring the Use of Artificial Intelligence to Improve Railroad Safety”. Retrieved from https://www.njdottechtransfer.net/2022/08/19/researchspotlightairailroadsafety

Rupi, F., Freo, M., Poliziani, C., & Schweizer, J. (2023). “Analysis of Gender-Specific Bicycle Route Choices Using Revealed Preference Surveys Based on GPS Traces.” Retrieved from https://www.sciencedirect.com/science/article/pii/S0967070X2300001X

Salazar-Miranda, A., Zhang, F., Maoran, S., & Ratti, C. (2023). “Smart Curbs: Measuring Street Activities in Real-Time Using Computer Vision,” Retrieved from https://www.sciencedirect.com/science/article/pii/S0169204623000348?casa_token=XPecGlOM6UQAAAAA:vnISsmV2aoJ3iVJefEeqjM24R5izcs66bvukCQObjuSWGTNokotT4CG_1h8UfLih16wn3FMg_Jo [DA1] [KR2] 

Von Hagen, L.A., Meehan, S., Younes, H., et. al. (2022), “Asbury Park Bike Lane Demonstration,” Retrieved from https://storymaps.arcgis.com/stories/c014811ac0c14735bc9c9adc2639e88f.

Younes, H., Noland, R., & Andrews, C. (2023). “Gender Split and Safety Behavior of Cyclists and E-Scooter Users in Asbury Park, NJ,” Retrieved from https://www.sciencedirect.com/science/article/abs/pii/S2213624X2300127X#b0055.

Younes, H., Noland, R., & and Von Hagen, L.A. (2023). “Are E-Scooter Users More Seriously Injured than E-Bike Users and Bicyclists?” Retrieved from https://policylab.rutgers.edu/are-e-scooter-users-more-seriously-injured-than-e-bike-users-and-bicyclists/.


Research to Implementation: The Use of Porous Concrete in Sidewalks

This Research to Implementation video presents an example of NJDOT-sponsored research and the effect such research has in addressing transportation-related issues within the State.

Pervious (or porous) concrete has been gaining popularity as a potential solution to reduce the amount of impermeable surfaces associated with sidewalks, reduce puddling, and potentially slow storm water surface runoff. As important as these benefits are to surface runoff mitigation, concerns exist as to the ability of pervious concrete to provide sufficient structural support and longevity for the expected service life of the sidewalks as well as its life cycle costs. The composition of pervious concrete can limit its mechanical strength and present challenges in its maintenance to achieve the expected service life.

With support from NJDOT’s Bureau of Research, researchers have looked at the benefits and challenges to utilizing porous concrete for sidewalks, and conducted a follow-up demonstration project. For more information about this research and the demonstration project, see: The Use of Porous Concrete for Sidewalks and Implementation of Porous Concrete for Sidewalks in New Jersey.

The Research to Implementation video series promotes the benefits of funded research to increase the safety of the traveling public, reduce costs, and increase efficiency.

Recap: 25th Annual NJDOT Research Showcase

The 25th Annual NJDOT Research Showcase provided an opportunity for the New Jersey transportation community to learn about the broad scope of academic research initiatives underway and share technology transfer activities being conducted by institutions of higher education partners and their associates. The annual event serves as a showcase to highlight the benefits of transportation research, including NJDOT’s own program. This event was an in-person event with a livestreaming option with sessions held from 9:00am-2:45pm on October 25, 2023.

This year’s Showcase theme, “Commitment to Safety,” served as the organizing framework for the speakers and panelists during the morning plenary session. Throughout the day the Research Showcase featured presentations on infrastructure, safety, mobility, and equity topics being performed by research faculty, staff, students, and NJ agencies. Several awards were presented in recognition of research and implemented innovations.

The Research Showcase Program Agenda provides more information on the day’s proceedings, including presented topics and invited speakers. Recordings of the plenary and breakout sessions, and the presentations and posters shared during the event can be found below.

MORNING

WELCOMING AND INTRODUCTORY REMARKS

David Maruca, Program Development Administrator, Rutgers Center for Advanced Infrastructure and Transportation, served as the moderator for the morning session, offering some housekeeping remarks and walked through the morning’s agenda.

Morning Plenary and Keynote

Andrew Swords, Director, New Jersey Department of Transportation Division of Statewide Planning, welcomed attendees to the 25th Annual NJDOT Research Showcase, explaining the purpose and theme of the event, “Commitment to Safety,” and acknowledging several parties, including NJDOT Bureau of Research staff, Rutgers-CAIT, and the leadership of NJDOT and FHWA for their planning and participation in the day’s event along with the research partners whose work was being showcased.

Diane Gutierrez-Scaccetti, Commissioner, New Jersey Department of Transportation, thanked several partners for their involvement in the event and reflected on the history of the Research Showcase Event on the occasion of the 25th Anniversary. In framing the day’s activities, Commissioner Gutierrez-Scaccetti recognized the event’s “Commitment to Safety” theme and the foundational importance of transportation for affecting positive change, improving the quality of life, and the shape of New Jersey’s transportation system. In her remarks, she appealed to attendees to advance community-centered transportation and to commit to considering the needs of ALICE (Asset Limited, Income Constrained, Employed) persons when devising research questions and in carrying out their day-to-day activities with the goal of planning, building and maintaining a more safe, equitable and sustainable transportation system.

Diane Gutierrez-Scaccetti, Commissioner, New Jersey Department of Transportation. Photo by Steve Goodman.

Robert Clark, Division Administrator, Federal Highway Administration New Jersey Division acknowledged the importance of the NJDOT Research Showcase’s “Commitment to Safety” theme. He described several policy and research commitments at U.S. DOT, FHWA Turner-Fairbanks Research Center and the Volpe Center that are intended to “double-down” on improving safety, reducing fatalities and strengthening the culture of safety in transportation. In closing out, Mr. Clark shared the USDOT Commissioner’s message that roadway deaths is a crisis that is urgent, unacceptable and preventable; those in attendance should see that their work and research into safety can prove that roadway fatalities need not be inevitable.

KEYNOTE ADDRESS

Dr. Allison E. Curry, PhD, MPH, Associate Professor of Pediatrics, Children’s Hospital of Philadelphia delivered the keynote address on the New Jersey Safety and Health Outcomes (NJ-SHO) Data Warehouse. In organizing her talk, she explained the vision behind the development of the data warehouse over the last 15 years, the data sources that have been employed, its innovative features that can support meaningful research, and her vision for future research and collaborations drawing upon the data warehouse platform.

Dr. Curry described how crash data can be linked to other data sets to extend the period of study about crashes. She explained the data warehouse has been built through an array of administrative data partnerships with NJ agencies (e.g, public health, hospital, motor vehicle, police, medicare and medicaid, etc.) that have been linked alongside rich community-level indicators available at the census tract level to create a robust data tool for traffic safety research.

Dr. Allison E. Curry, PhD, MPH, Associate Professor of Pediatrics, Children’s Hospital of Philadelphia. Photo by Steve Goodman.
New Jersey Safety and Health Outcomes (NJ-SHO) Data Warehouse. Dr. Allison E. Curry, PhD, MPH, Associate Professor of Pediatrics, Children’s Hospital of Philadelphia

Her talk highlighted some of the limitations of crash reports that explain the need for data integration with other administrative record sources. She emphasized the longitudinal features of the data warehouse and explained how its linkages to health and motor vehicle records makes it possible to study specific populations segments — for example, teens on the autism spectrum. In her example, she described her research demonstrating how the data sets could be used to investigate the percentage of teens with autism who acquired driver licenses to increase their travel independence. She also could compare whether crash rates were comparable between this group and other teens in their age cohort at 12 months and 48 months from receipt of a license.

Dr. Curry also highlighted data limitations on reporting of race and ethnicity on NJ crash and licensing data and how other data sources (e.g., hospital discharge, electronic health records, birth and death data, etc. ) can be used to look at race and ethnic differences in non-fatal crash outcomes.  In doing so, she highlighted how a probability-based algorithm, Bayesian Surname Geocoding (Sartin 2021), developed by the RAND Corporation, has been applied to estimate the race and ethnicity of driver licenses and address a source of race and ethnic bias in hospital record reporting due to varying levels of hospital usage.

Dr. Curry touched upon several of NJ SHO’s innovative features that can enable research.  Among other points, she contrasted the “urban planning lens” which considers the place in which an accident occurred with the “public health lens” which seeks information about persons who are crash victims and where they live.

She also offered illustrative examples of how the NJ-SHO can be linked to vehicles to examine types of crashes, vehicle types and the injuries incurred which can reveal differences among more vulnerable populations (e.g, youth, elderly, poor) from other populations.

Dr. Curry closed her talk with a sneak preview of a new interactive data dashboard, NJ-SHO Center for Integrated Data, currently in development in association with the NJ Division of Traffic and Highway Safety. She noted how the dashboard tool will help practitioners efficiently use available data sets in ways that will mirror the metrics of the NJ Strategic Highway Safety Plan with a focus on persons as well as community resilience and social vulnerability equity-oriented measures.

Dr. Curry responded to questions in a Q&A session that followed her keynote remarks.

MORNING SESSION PANEL DISCUSSION

An interactive panel discussion, “How is New Jersey Department of Transportation Addressing Safety?” followed the keynote session with state NJDOT staff representatives who presented examples of the safety initiatives underway at NJDOT and reflected on persistent challenges and opportunities for addressing transportation safety in New Jersey.

The panelists included:

  • Andrew Swords, Director, New Jersey Department of Transportation Division of Statewide Planning.
  • Syed Kazmi, Section Chief, New Jersey Department of Transportation Division of Traffic Engineering
  • Kurt McCoy, Supervising Engineer, New Jersey Department of Transportation Division of Operations Support
  • Sangaran Vijayakumar, Project Management Specialist 3, New Jersey Department of Transportation Division of Project Management
  • Hirenkumar Patel, Principal Engineer, New Jersey Department of Transportation Division of Transportation Mobility
Safety Panel
How is New Jersey Department of Transportation Addressing Safety?

Participants responded to a series of questions posed by the moderator and by the audience members.

Panelists shared their views on how the New Jersey Department of Transportation addresses safety. Photo by Steve Goodman.

AWARDS

The program continued as Dr. Giri Venkiteela Research Scientist, Bureau of Research, New Jersey Department of Transportation announced several awards given in recognition of research, innovation and implementation efforts. Below is a listing of the award winners presented at this year’s showcase:

  • 2023 Outstanding University Student in Transportation Research Award – Alissa Persad, Rutgers University, Ms. Persad was being recognized in part for her valued contributions to the Innovative Materials for Quick Patching and Repair of Concrete project.
  • 2023 NJDOT Research Implementation Award – Dr. Hao Wang, Rutgers University Energy Harvesting on New Jersey Roadways. This project identified potential energy harvesting technology for applications on roadways and bridges and conducted feasibility analysis and performance evaluation of the selected technologies for large-scale and micro-scale energy generation.
  • 2023 Best Poster Award – Alyssa Yvette Sunga, Rowan University, Properties of Cementitious Materials with Reclaimed Cement. This poster described research activities that obtained recycled concrete; determined the chemical composition of reclaimed cement; partially replaced ordinary Portland cement with reclaimed cement in cement paste and mortar; and determined the fresh and hardened properties of cement paste and mortar through tests measuring flowability, initial setting time, heat of hydration, and compressive strength.
  • 2023 Research Champion Excellence Award – Thomas Bushar, New Jersey Department of Transportation, Materials. This award recognizes Mr. Busher’s dedication while serving as a Technical Advisory Panel member for The Evaluation of Different Paint Systems for Over-Coating Existing Structural Steel project. The award notes that his commitment greatly contributed to the success and implementation of this research project.
  • 2023 NJDOT Build a Better Mousetrap Award – Gerald Oliveto, P.E. New Jersey Department of Transportation, Moveable Bridge Unit. The “Route 71 Over Shark River Road Diet” is a road diet project that preserves an old historic drawbridge while improving safety and saving money.  When the Route 71 Drawbridge over Shark River between Belmar and Avon-by-the-Sea in Monmouth County suffered a mechanical failure in September 2021, engineers worked quickly to design and implement a solution that would both preserve the drawbridge and keep it in safe operation. The traffic load needed to be redistributed and balanced properly across the span to keep the bridge opened. NJDOT implemented a road diet across the bridge, which allowed the Department to address several safety issues. Traffic over the bridge was reduced from one northbound lane and two southbound lanes to one lane in each direction. Signal timings were adjusted, safety improvements at surrounding intersections were installed, and highway signage was enhanced. In addition, bike lanes that had previously ended abruptly were carried across the drawbridge utilizing an innovative bicycle-safe grid, a first-of-its-kind achievement in New Jersey. Through this $150,000 project completed in May 2022, the Route 71 over Shark River Road Diet project improved traffic flow, increased safety, and reduced congestion in a busy tourist area.
Awards Ceremony

Presentation of 2023 Awards

PRESENTATION OF AWARDS

2023 Outstanding University Student in Transportation Research Award, Alissa Persad, Rutgers University, Innovative Materials for Quick Patching and Repair of Concrete. Photo by Steve Goodman.
2023 NJDOT Research Implementation Award, Dr. Hao Wang, Rutgers University Energy Harvesting on New Jersey Roadways. Photo by Steve Goodman.
2023 Best Poster Award, Alyssa Yvette Sunga, Rowan University, Properties of Cementitious Materials with Reclaimed Cement. Photo by
Steve Goodman.
2023 Research Champion Excellence Award, Thomas Bushar, New Jersey Department of Transportation, Materials. Rajesh Kabaria accepted award on his behalf. Photo by Steve Goodman.
2023 NJDOT Build a Better Mousetrap Award, Gerald Oliveto, P.E. New Jersey Department of Transportation, Moveable Bridge Unit. The “Route 71 Over Shark River Road Diet.” Photo by Steve Goodman.

AFTERNOON 

In the afternoon, concurrent break-out sessions were held and research presentations were given on the topics of Equity & Mobility, Infrastructure, and Safety in transportation. Students and researchers at New Jersey’s colleges and universities also presented their research objectives, methods and findings in a concurrent poster session offering those in attendance an opportunity to learn more about ongoing and recently completed research and interact with the researchers.

INFRASTRUCTURE BREAKOUT

Infrastructure Sessions
Development and Analysis of Low Embodied Carbon Concrete Mixtures for Use in Transportation Applications. Matthew P. Adams, New Jersey Institute of Technology
Asphalt Pavement Pothole Repair with Recycled Material and Preheating. Xiao Chen and Hao Wang, Rutgers University
Rapid Assessment of Infrastructure Using NDT Methods. Manuel Celaya, Advanced Infrastructure Design, Inc.

EQUITY & MOBILITY BREAKOUT

Equity & Mobility Sessions
Comparative Analysis of Arterial Characteristics to Evaluate Road Diet Lane Reduction Potential. Thomas Brennan, The College of New Jersey
A Vehicle Trajectory Stitching and Reconstruction Method for Digital Twin Applications with High-Resolution Roadside LiDAR Data. Anjiang Chen, Rutgers University
Developing Indicators for Comprehensive Evaluation of Equity in Transportation System. Catherine Abacan and Ruqaya Alfaris, Rowan University

SAFETY IN TRANSPORTATION BREAKOUT

Safety in Transportation Sessions
Unveiling Perceived Travel Safety for Micromobility Users: A Rider-Centered Exploration. Wenwen Zhang, Rutgers University
Determining Key Factors Linked to Injury Severity in Intersection-Related Crashes in NJ. Deep Patel, Rowan University
Understanding Crash Factors in Disadvantaged Communities: An Examination of Socioeconomic Disparities and Road Safety. Ruqaya Alfaris, Rowan University

2023 POSTER PRESENTATIONS

Optimizing Road Infrastructure: A Conceptual Simulation-Based Study of Dynamic Transit Lanes for Connected Private Vehicles
 Connected Vehicles Data: A New Horizon for Estimating Traffic Counts
Properties of Cementitious Materials with Reclaimed Cement
Investigating Performance of Cold In-Place Recycled Asphalt Sections in Accelerated Pavement Testing Using Finite Element Modeling
Investigating the Severity of Curve-Related Roadway Departure Crashes: The Role of Driver Distraction, Automation Levels, and Environmental Conditions
Development of High-Frequency Electromagnetic Induction Technology for Nonintrusive Geophysical Ground Investigation in Cold Regions
Study of the Failure Mechanisms for Inducing Rockfall Hazard in New Jersey Area
Machine Learning Based Structural Health Monitoring of Rocking Bridge System under Seismic Excitation
Truck Parking Availability Prediction Model for Harding Truck Rest Area
Prediction of Critical Strains of Flexible Pavement from Traffic Speed Deflectometer Measurements
Design Study and Potential Implementation of Photovoltaic Noise Barrier for Sustainable Highway
Computer Vision Based Near Miss Detection Among Mixed Traffic Flows Within Intersections
Segment Anything Model for Pedestrian Infrastructure Inventory: Assess Zero-Shot Segmentation on Multi-Mode Geospatial Data


The 25th Annual Research Showcase was organized and sponsored by the NJDOT Bureau of Research in partnership with the New Jersey Local Technical Assistance Program (NJ LTAP) at the Rutgers Center for Advanced Infrastructure and Transportation (CAIT) and co-sponsored by the Federal Highway Administration.

The NJ Transportation Ideas Portal is Open to Your Ideas!

The New Jersey Department of Transportation’s (NJDOT) Bureau of Research invites you to share your research and innovation ideas on the NJ Transportation Ideas Portal.

We seek to fund RESEARCH IDEAS that lead to implementation – to the testing and adoption of new materials and technologies, to better specifications and to greater efficiency. We strive to discover and advance feasible solutions for more durable infrastructure, greater environmental protection and resilience, and improved mobility and safety for residents, workers and visitors.

We encourage you to suggest INNOVATION IDEAS. We seek to find strategies to advance deployment of innovations and knowledge transfer in transportation. We work with the New Jersey State Transportation Innovation Council (NJ STIC) whose mission is to identify, evaluate, and where possible, rapidly deploy new technologies and process improvements that will accelerate project delivery and improve the quality of NJ’s transportation network. Innovation Ideas will be vetted for next steps which might include research or supporting an initiative to deploy a new technology or process improvement to accelerate innovation.

WHO CAN SUBMIT IDEAS? NJDOT’s research customers and other interested transportation practitioners are encouraged to submit a research or innovation idea. The portal should be of interest to NJDOT, MPOs, county and local governments, and other transportation subject matter experts from university, industry and trade organizations and other NGOs. The portal is also open to the public.

WHO ARE RESEARCH CUSTOMERS? Subject matter experts from NJDOT, NJ TRANSIT, or the NJ Motor Vehicles Commission are often our research customers. Research ideas typically must have a champion among our research customers. Ideally, a “champion” is a responsible individual within a division, bureau or unit who is prepared to sponsor or advance a research idea from its inception to study completion.

COLLECTING IDEAS NOW! Our research and innovation teams review submitted ideas for possible funding and other actions throughout the year. The last day to submit research ideas for the next round of funded transportation research is December 31, 2023.

Our research and innovation teams review submitted ideas for possible funding and other actions throughout the year.

REGISTER TO PARTICIPATE AND SUBMIT AN IDEA.  Once you are registered, you may submit ideas at any time.  If you registered previously, you should not need to register again.  Click on the “+” button at the top of the page to register. Only registered participants may submit a new idea or vote on other ideas to show your support. Register at the NJ Transportation Ideas here:  https://njdottechtransfer.ideascale.com/

QUESTIONS ABOUT HOW TO REGISTER?
Email: ideas@njdottechtransfer.net

For more information about NJDOT Bureau of Research, visit our website: https://www.state.nj.us/transportation/business/research/

Or contact us:  research.bureau@dot.nj.gov or (609) 963-2242

NJDOT Tech Talk! Webinar – Research Showcase: Lunchtime Edition 2023

On April 26, 2023, the NJDOT Bureau of Research hosted a Lunchtime Tech Talk! webinar, “Research Showcase: Lunchtime Edition!”. The event featured three important research studies that NJDOT was not able to include in the NJDOT Research Showcase virtual event held last October. The Showcase serves as an opportunity for the New Jersey transportation community to learn about the broad scope of academic research initiatives underway in New Jersey.

Video Recording: 2023 Research Showcase Lunchtime Edition

The three research studies explored issues at the intersection of transportation and the environment and the advancement of sustainable transportation infrastructure. The presenters, in turn, shared their research on the design and performance evaluation results of harvesting energy through transportation infrastructure; the properties of various materials used in roadway design treatments to effectively quantify and mitigate stormwater impacts of roadway projects; and analytical considerations inherent in estimating road surface temperatures to inform the development of a winter weather road management tool for NJDOT. After each presentation, webinar participants had an opportunity to pose questions of the presenter.


Presentation #1 – New Design and Performance Evaluation of Energy Harvesting from Bridge Vibration by Hao Wang, Associate Professor, Civil and Environmental Engineering, Rutgers Center for Advanced Infrastructure and Transportation (CAIT)

Dr. Wang noted that energy harvesting converts waste energy into usable energy that is clean and renewable for various transportation applications. Energy harvesting projects can be large scale (solar or wind energy solutions) or micro-scale (providing power for lighting, self-powered sensor devices, and wireless data transfer).

In this project, the large scale application considered the use of photovoltaic noise barriers (PVNBs) which integrate solar panels with noise barriers to harvest solar energy. His research developed energy estimation models at the project- and state-level for a prototypical design installation of noise barriers.

In his presentation, Dr. Wang focused on the micro-scale application that employed piezoelectric sensors on bridge structures. He noted that piezoelectric energy harvesting can be achieved by compression or vibration. He explained that traffic and winds cause roadway bridges to vibrate. This movement subjects the piezoelectric sensors to mechanical stresses or changes in geometric dimensions which create an electric charge.

Piezoelectric energy harvesting is affected by the material, geometry design of the transducer, and external loading. Instead of embedding sensors in pavements, the researchers sought to attach the sensors to the bridge structure imposing less impact on the host structure and increasing the ease of installation. They developed and evaluated new designs of piezoelectric cantilevers to create a range of resonant frequency to match with bridge vibration modes.

Multiple degree-of-freedom (DOF) cantilever designs were tested in the laboratory, and in full-scale tests. The goal was to customize the design to maximize power outputs resulting from bridge vibrations. Multiple cantilever design options were examined with adjustable masses. Simulation models were developed for estimating energy harvesting performance and to facilitate the optimization of mass combinations through quantitative models.

The researchers used finite element models to simulate the effect, and assessed the model in the laboratory to manage the voltage output of various designs. Bridges have multiple vibration frequencies under different vibration modes, on the bridge structure and the span. A full-scale bridge test was conducted using the Rutgers-CAIT Bridge Evaluation and Accelerated Structural Testing lab (BEAST) to give sample voltage outputs from cantilevers.

Future research will be needed to explore the effect of loading speed that takes into consideration the variable speeds on a bridge something that was not captured in the laboratory testing.

Findings of the research included: multiple degree of freedom (DOF) cantilevers can generate considerable energy when resonant frequencies match vibrational frequencies of the bridge structure; finite element modeling can predict resonant frequencies of multiple-DOF cantilevers as validated by experiments and ensures that numerical models can be used to explain the relationship between resonant frequency and mass combination for optimized design; and the proposed cantilever designs and optimization approach can be used for piezoelectric energy harvesting considering a variety of vibration features from bridges under different external conditions.

Dr. Wang responded to questions following his presentation:

Q. How far below the asphalt are the sensors placed and how often do they need to be replaced?
A. For this project, the installation in this phase used a magnetic fixture to attach the cantilever to the girder.  The installation procedure was easy for this phase.  For a field installation, we will need to consider more thoroughly the mount and durability but did not need to address this during this phase and we do not have real-world data now to share about that.

Q. Would the vibrations be amplified with the cables?
A. The cables on the real bridge – if we attached to the cable the vibrations would be less, which is why we attached them to the girder.


Presentation #2 – Impacts of Vegetation, Porous Hot Mix Asphalt, Gravel and Bare Soil Treatments on Stormwater Runoff from Roadway Projects by Qizhong (George) Guo, Professor, Civil and Environmental Engineering, Rutgers Center for Advanced Infrastructure and Transportation

Click for PDF

Dr. Guo described the effect of increased impervious coverage in urban locations that leads to increased surface water runoff. Transportation agencies are required to assess and mitigate the stormwater runoff impacts of roadway projects. The project explored the effect on runoff of use of gravel, vegetation, porous Hot Mix Asphalt (HMA), and bare soil. Areas where these materials would be used include the roadway right-of-way, medians, and beneath guiderails.

Variables explored in lab testing included subsoil hydraulic conductivity, rainfall intensity and rainfall duration. The researchers used the Curve Number (CN) method for estimating direct runoff from rainstorms. Lab testing involved a column of soil with little lateral flow and limited depth to the level representing the water table. To apply lab findings to field conditions, the regression equation of Curve Number versus the infiltration rate obtained from the laboratory measurements can be applied after replacing the laboratory-measured infiltration rate with the field-measured subsoil hydraulic conductivity or assigned hydrologic soil groups.

This research resulted in Curve Numbers for bare soil and vegetation similar to the established CNs for dirt (including right-of-way) and open space (lawns, fair condition). The estimated CNs for gravel were significantly smaller than the established CNs for gravel (including right-of-way). The research resulted in CNs for porous HMA but no comparison can be made as there is no established CN for this material. The project could help NJDOT in seeking approval of the Curve Numbers for gravel and porous HMA from regulatory agencies. In addition, the study affirmed the use of pervious surfaces and the effectiveness of stormwater runoff reduction to restore natural hydrology.

Following the presentation, Dr. Guo responded to questions asked through the chat feature:

Q. What are preventative measures to avoid porous HMA clogging?
A. Sediment source control is needed to prevent dirt and dust from entering the porous HMA. If the area around the pavement is subject to erosion, runoff carries this dirt or sand into the material. If the material becomes clogged, a vacuum is needed to clean it.

Q. Can we disperse runoff in roadway drainage systems as opposed to collection?
A. There are several ways to disperse runoff, such as by the use of rain gardens, a horizontal spreader, or use of a stone/gravel strip to spread the runoff.

Some questions were submitted in the Chat and, due to time constraints, were answered by Dr. Guo after the Tech Talk.

Q. We recently had a project meeting during concept development where we suggested porous asphalt for guide rail base. Another team mentioned they would prefer we not use PHMA due to it clogging over time and basically becoming HMA. What research has been done on PHMA effectiveness over time, and what can be done to remedy reduced flow (if it does occur)?
A: The clogging of porous hot mix asphalt (PHMA) and other porous pavement varieties is undeniably a significant and pressing issue. Our study for NJDOT did not tackle the problem of clogging, but other researchers have conducted relevant investigations, and more targeted research is anticipated. The most effective method to reduce clogging is by preventing excessive coarse sediment from entering PHMA and other porous pavements. Special care should be taken to maintain the surrounding landscape in order to mitigate soil erosion, and not to apply sand to any of the road surfaces for snow abatement. Alternatively, sediment in the runoff can be captured or filtered using a swale or gravel strip before it enters the PHMA or other porous pavement areas. Implementing a proactive inspection and monitoring system for clogging is also essential.

In cases where PHMA or other porous pavements become clogged, a vacuum street sweeper or regenerative air sweeper can be employed to dislodge and remove the solid materials. However, traditional mechanical sweepers should be avoided, as they may cause the solids to break down or force particulates deeper into the porous spaces, exacerbating the clogging issue in porous pavements.

Q. Did you use the same course stone mix in the NJDOT specs for the course stone non-vegetative surface. I assume you are calling this gravel.
A: Yes, the NJDOT construction specifications were adhered to in the design of the laboratory setup for all four land treatment types: gravel, porous hot mix asphalt, vegetation, and bare soil. These specifications can be found in the “Roadway Design Manual (2015)”, “Standard Construction Details (2016)”, and “Standard Specifications for Road and Bridge Constructions (2019)”. Comprehensive details are provided in Table 13 in Appendix A of our Final Report for the research project (FHWA-NJ-2023-004).

Q. What compaction did you use for the porous HMA?  We usually use only a small portable tamper machine in the field with about 2 passes.
A. In our laboratory, a gyratory compactor was employed for the compaction of the porous HMA samples tested. Two relevant sentences in our Final Report for the research project (FHWA-NJ-2023-004) state: “For the porous asphalt land treatment, cylindrical porous Hot Mix Asphalt (HMA) gyratory samples with a diameter of 6 in and a depth of 4 in were manufactured at Rutgers CAIT Asphalt Pavement Lab. The mix design utilized to manufacture the HMA met the requirements of the Open-graded Friction Course in the Updated Standard Specifications for Road and Bridge Construction (2007).”

Q: Can this report be used to get acceptance of porous HMA by DEP?
A: Yes, although further dialogue with NJDEP, NRCS, and other relevant agencies or organizations may be necessary for the ultimate acceptance.

Q: NJDOT Materials lab did a study of various ages of porous HMA in the field and found out that it did not clog over an 8 year period.  It appeared to be self-cleaning.
A: I appreciate the information you provided. The likelihood of porous HMA clogging is closely related to the volume and size of solids, sediment, or particulates entering it. A minimal amount of fine particulates is unlikely to cause serious or rapid clogging issues in porous HMA. To my knowledge, there is no “self-cleaning” mechanism inherent in porous HMA.

Q: What about the contamination in runoff water which will penetrate in subsoil?
A: Contaminants in runoff water should not be allowed to infiltrate the subsoil. Highly contaminated runoff must not directly enter land treatments (LTs), green stormwater infrastructure (GSI), stormwater Best Management Practices (BMPs), or stormwater control measures (SCMs). Instead, these systems will treat mildly contaminated runoff as it passes through them. Consequently, the runoff water will achieve a relatively high level of purity before it infiltrates the subsoil.


Presentation #3 – Practical Considerations of Geospatial Interpolation of Road Surface Temperature for Winter Weather Road Management by Branislav Dimitrijevic, Assistant Professor, Civil and Environmental Engineering, New Jersey Institute of Technology (NJIT) and Luis Rivera, Analyst Trainee, NJDOT Transportation Mobility, Transportation Operations Systems & Support

Click for PDF

Mr. Rivera provided background on NJDOT’s Weather Savvy Road System that addresses the need for proactive winter road maintenance and the wide variation in road conditions throughout the state. There are only 48 stationary Road Weather Information Systems (RWIS) stations across the state in areas that are deemed essential. They provide information on road conditions (wet or dry), and road temperature. The Weather Savvy Road System integrates stationary RWIS and mobile RWIS (MRWIS) to track road conditions in real time, provide data visualization to operators to inform decision-making, and assist in planning road management.

In 2017, NJDOT received a USDOT Accelerated Innovation Deployment grant for implementation of FHWA’s Every Day Counts Round 4 Weather Savvy Roads Integrating Mobile Observations (IMO) innovation. The agency deployed Internet of Things (IoT) and Connected Vehicle technology to improve road weather management. NJDOT installed sensors and dash cameras on 24 fleet vehicles to pick up air temperatures, road temperatures, surface condition, and road grip, and portable PC equipment to analyze and report this information to improve safety for the traveling public and inform decision-making. Road surface temperature is the most indicative measure of road condition.

Dr. Dimitrijevic discussed research undertaken to gather road surface temperatures using Kriging, a geospatial interpolation model. The goal was to discover a way to extrapolate the information collected from the sensors to provide estimated road surface temperatures across the entire road network within NJDOT’s jurisdiction.

The researchers collected data from RWIS/MRWIS and other data available, including land coverage, elevation, etc., that can affect road surface temperatures (RST). They sought to use a Kriging Interpolation and Machine Learning Model to give estimated RSTs over the network to inform planning and evaluation of winter road maintenance efforts. Variability in RST across the analysis region is a big factor. Researchers needed to find a function that fit the variability between the data points, and use that to estimate the parameter value at any particular point.

Dr. Dimitrijevic discussed the differences between three Kriging methods: Ordinary Kriging and Universal Kriging, the simplest and fastest to calculate; regression Kriging which uses additional factors, besides distance, that will affect RST; and Empirical Bayesian Kriging that uses Bayesian inference to calculate parameters, but also calculates the probability of making an error.

All three Kriging methods assume that for any correlation between a given parameter that you are trying to estimate in a given area, there is a relationship between the values of that parameter at different points that depends on the actual location of the points, or distance between points. The method uses the known value of surrounding parameter points, for example, the road surface temperature at these points, and measures the distance between these points of known parameter value to estimate the parameter (RST) at the unknown point. Kriging assumes a statistical relationship involving the distance between RWIS stations.

Researchers conducted case studies using RST interpolation of stationary RWIS data by driving between RWIS locations, and then expanded the RWIS coverage of mobile sensors during a winter storm event. They found the best results came from combining RWIS and mobile RWIS data. They found Regression Kriging to be helpful for including other factors (the most statistically significant being vegetation type, land cover type, distance to water, and elevation). Increasing the mobile RWIS records reduced the error level, and this finding resulted in a recommendation to increase the number of mobile sensors on NJDOT’s fleet.

Kriging was effective in capturing the spatial variation in the dataset. An error of one degree Fahrenheit still needs to be addressed. The researchers continue to look into solutions in ongoing research which will explore additional interpolation methods, integration of short-term past predictions, and a bi-level interpolation using stationary RWIS data at a regional scale and the mobile RWIS data to make adjustments to the local scale.

The model that performed best was implemented in a web-based map tool that gathers data in real time and refreshes the estimated road surface temperature every 10-15 minutes, providing a map and the ability to download data. When complete, this tool will become part of the toolbox for Operations, Maintenance and Mobility division.

Dr. Dimitrijevic answered questions following his presentation:

Q. How is the dew point and frost point measured by the sensor?
A. Dew point is not measured; there are statistical models that calculate readings of air temperature, air humidity and pressure to determine dew point or frost point. Dew point and frost point are the same thing. The term used depends on the temperature.

Q. What other interpolation models, besides Kriging, will you be looking at?
A. We are looking at a combination of machine learning and geo-statistical modeling. There is also bi-level modeling that uses one method to regress the regional scale estimate, and another to use the localized readings to adjust the estimates for a local roadway. These methods require more computation time, but we are looking for models that can calculate in real time for tactical management purposes.

A recording of the webinar is available here.


Resources

Cowan, S., Catlett., S. Ahmed, R., Murphy., T., Dimitrijevic, B., Besenski, D., Spasovic, L., and Zhao, L. (2022).  Weather-Savvy Roads Pilot Program, Final Report.  Retrieved from: https://www.njdottechtransfer.net/wp-content/uploads/2022/11/WeatherSavvy_FinalReport_20220613.pdf

Qizhong (George) Guo, Robert Miskewitz, John Hencken, Lin Zheng, Diego Meneses, (2023). Evaluation of Coefficient Related to Runoff from Roadway Projects [Final Report].  Retrieved from: https://www.njdottechtransfer.net/wp-content/uploads/2023/05/FHWA-NJ-2023-004.pdf

Wang, H., Guo, L., and Soares, L. (2023).  Energy Harvesting on New Jersey Roadways [Final Report].  New Jersey Department of Transportation Bureau of Research.  Retrieved from: https://www.njdottechtransfer.net/wp-content/uploads/2023/05/FHWA-NJ2023-001.pdf

Wang, H., Guo, L., and Soares, L. (2023).  Energy Harvesting on New Jersey Roadways [Technical Brief].  New Jersey Department of Transportation Bureau of Research.  Retrieved from: https://www.njdottechtransfer.net/wp-content/uploads/2023/05/FHWA-NJ2023-001_TB.pdf

Research Spotlight: NJ Transit Grade Crossing Safety

A recently completed research study on NJ TRANSIT grade crossing safety focuses on identifying locations for rail grade crossing elimination. Researchers from Rutgers’ Center for Advanced Infrastructure and Transportation (CAIT), Asim Zaman, P.E., Xiang Liu, Ph.D., and Mohamed Jalayer, Ph.D., from Rowan University, developed a methodology using 20 criteria to narrow a list of 100 grade crossings to ensure appropriate identification for closure. The process helps NJ TRANSIT and New Jersey Department of Transportation (NJDOT) to direct limited funds to areas of greatest need to benefit the public.

Across the country, 34 percent of railroad incidents over the past ten years have occurred at grade crossings. The elimination of grade crossings can improve public safety, decrease financial burdens, and improve rail service to the public.

According to the proposed methodology, the 20 crossings recommended for closure located in Monmouth County (60%), Bergen County (25%), and Essex County (25%).

According to the proposed methodology, the 20 crossings recommended for closure located in Monmouth County (60%), Bergen County (25%), and Essex County (25%).

The researchers ranked grade crossings in New Jersey using the following data fields: crash history, average annual daily traffic, roadway speed, roadway lanes, length of the crossing’s street, weekday train traffic, train speed category, number of tracks, access to train platforms, intersection angle, distance to alternate crossings, distance to emergency and municipal buildings, whether emergency and municipal buildings are on the same street, and date of last or future planned signal and surface upgrades. This process resulted in a final list of 20 grade crossings eligible for elimination.

To understand how this study will be used, we conducted an interview with NJTRANSIT personnel Susan O’Donnell, Director, Business Analysis & Research, Ed Joscelyn, Chief Engineer – Signals, and Joseph Haddad, Chief Engineer, Right of Way & Support.

Q. How will the report inform decision-making? 

It is important to have solid research and strong evaluation criteria, such as developed by this study, on which to base decisions for grade crossing elimination. In addition to the study, we looked at what other state agencies and transit agencies have done with grade crossing elimination, as well as criteria recommendations from Federal Highway Administration (FHWA) and Federal Railroad Administration (FRA). Following up on this study, NJ TRANSIT and NJDOT are considering next steps that would be needed to close the 20 identified grade crossings. In New Jersey, the Commissioner of Transportation has plenary power over the closing of grade crossings.

Q. What other information will be needed to assess these locations? 

Local concerns about grade crossing elimination tend to focus on traffic re-routing, including the possible impacts on neighborhoods, time needed to reach destinations, and emergency vehicle access to all parts of a community. The criteria established by the study addressed these areas of concern. Prior studies have determined that the road networks around the identified locations are adequate to accommodate re-routed traffic. The current research study took into account the findings from those prior studies. As each project moves forward, NJDOT will determine if additional information will be needed.

Q. Is elimination of any of these grade crossings part of NJ TRANSIT’s capital program? 

All of the closings are part of the capital program. Funding for the grade crossing elimination comes from the federal government and NJ TRANSIT. NJ TRANSIT funding is in place to close the crossings.

Q. Are there benefits of the research study beyond identification of the 20 grade crossings?

The research study developed the criteria and process for identifying grade crossings for elimination. This framework can be used in the future to assess other grade crossings for possible elimination. NJ TRANSIT is grateful to NJDOT for funding this important research project to improve safety.

For more information on this research study, please see the resources section below.


Resources

Zamin, A., Alfaris, R., Li, W., Liu, Z. Jalayer, M., Hubbs, G., Hosseini, P., Calin, J.P., Patel., S. (2022). NJ Transit Grade Crossing Safety. [Final Report].  New Jersey Department of Transportation, Bureau of Research.  Retrieved from https://www.njdottechtransfer.net/wp-content/uploads/2023/02/FHWA-NJ-2022-005.pdf

Liu, Z., Jalayer, M., and Zamin, A. (2022). NJ Transit Grade Crossing Safety. [Technical Brief]. New Jersey Department of Transportation, Bureau of Research.  Retrieved from https://www.njdottechtransfer.net/wp-content/uploads/2023/02/FHWA-NJ-2022-005-TB.pdf

24th Annual NJDOT Research Showcase

The 24th Annual NJDOT Research Showcase provided an opportunity for the New Jersey transportation community to learn about the broad scope of academic research initiatives underway and share technology transfer activities being conducted by institutions of higher education partners and their associates. The annual event serves as a showcase to present the ongoing initiatives and benefits of the NJDOT Research program. This event was an in-person event with a livestreaming option with sessions held from 9:00am-2:45pm on October 26, 2022.

This year's Showcase theme, "Advancing Equity in Transportation" served as the organizing framework for the keynote speaker and panelists during the morning plenary session. Throughout the day the Research Showcase featured presentations on infrastructure, safety, mobility and equity topics being performed by research faculty, staff, and students and NJ agencies. Several awards were presented in recognition of research and implemented innovations.

The Research Showcase Program Agenda provides more information on the day's proceedings, including presented topics and speakers.  Recordings of the plenary and breakout sessions, and the presentations and posters shared during the event can be found below.


MORNING

Mike Russo, NJDOT Assistant Commissioner, Planning, Multimodal, and Grants Administration, welcomed attendees to the Research Showcase event.

Parth Oza, Assistant Commissioner, Capital Program Management, provided opening remarks focusing on ways that NJDOT has embedded equity in the project delivery process. Mr. Oza emphasized the importance of gathering input from communities affected by transportation projects throughout all project phases, using grant applications to address the impact of flooding on disadvantaged communities, and planning for the safety of all road users through the agency’s Complete Streets policy.

Valeriya Remezova, Deputy Division Administrator, Federal Highway Administration's New Jersey Division congratulated NJDOT for receiving the FHWA and AASHTO Innovative Initiative 2022 STIC Innovation Excellence Award. She recognized NJDOT research initiatives with an equity focus and noted New Jersey’s Metropolitan Planning Organization initiatives that advance equity.

Keith Benjamin, Associate Administrator for Highway Policy and External Affairs, Federal Highway Administration provided the keynote address. Mr. Benjamin discussed the Infrastructure Investment and Jobs Act and the opportunities to use this funding to address equity in transportation planning, project development, and other activities. He noted that the funding allows for new ideas of transportation to become a reality, and looks forward to subsequent policy embedding these changes in people’s everyday transportation experience. He noted the program’s success will be measured by improvements such as people being able to cross the street safely, mitigation of unsafe corridors, availability of bus shelters, and repaving of dangerous streets. He offered several examples of local initiatives where collaboration among partner agencies and organizations and involvement of local residents in the process resulted in more equitable projects.

Mr. Benjamin responded to several questions in a Q&A session that followed his keynote remarks.

Plenary Session Recording

Morning Session Presentation

Keith Benjamin, FHWA Associate Administrator for Highway Policy and External Affairs with Assistant Commissioner Michael Russo. Photo by Steve Goodman.
Keith Benjamin, FHWA Associate Administrator for Highway Policy and External Affairs with Assistant Commissioner Michael Russo. Photo by Steve Goodman.
Keith Benjamin and the host moderator, David Maruca, discussed the Bi-Partisan Infrastructure Bill, the USDOT Equity Action Plan, and the safety benefits of Complete Streets, among other topics in a lively Q&A session that followed Mr. Benjamin’s Keynote remarks. Photo by Steve Goodman.
Keith Benjamin and the host moderator, David Maruca, discussed the Bi-Partisan Infrastructure Bill, the USDOT Equity Action Plan, and the safety benefits of Complete Streets, among other topics in a lively Q&A session that followed Mr. Benjamin’s Keynote remarks. Photo by Steve Goodman.

An interactive panel discussion, "Perspectives on Advancing Equity in Transportation," followed the keynote session with state, local and transportation management association (TMA) representatives who presented examples of the equity initiatives underway in their organization and reflected on some of the continuing challenges and opportunities for advancing equity in transportation in New Jersey. The panelists included:

  • Elkins Green, Director, Environmental Resources, New Jersey Department of Transportation. Green served as the Moderator for the session.
  • Veronica Murphy, Director’s Office, Division of Local Aid & Economic Development, New Jersey Department of Transportation. Ms. Murphy shared a short video of the organization of Local Aid & Economic Development and provided an overview of the role that her office plays in providing grant funding for transportation projects. Ms. Murphy noted that equity considerations are embedded in the distribution of funding and in the process of providing technical assistance to communities through the Local Aid Resource Center.
  • Krishna Murthy, President, EZ Ride described the mission and various activities of his TMA and focused on the organization’s EZ Ryde4Life program that assists older adults by coordinating with Lyft and Uber to provide rides. EZ Ride is trying to make the program more accessible to individuals who are paying directly for the program and have no sponsoring organization and described the affordability challenges for the users and operator.
  • Andrew Tunnard, Assistant Commissioner, Transportation Operations Systems & Support, New Jersey Department of Transportation. Mr. Tunnard spoke about the Trenton MOVES project, an autonomous vehicle system that is being planned to offer transit shuttle services for an urban core population in the City of Trenton that tends to have one or no cars and spends a high proportion of their income on transportation to reach regional employment and other opportunities.
  • Byron Nicholas, Supervising Transportation Planner, Hudson County Engineering described the County’s efforts to advance equity through project prioritization, public involvement, multimodal safety.

Participants responded to a series of questions posed by the moderator and by the audience members.

Panelists discussed equity initiatives underway in their organization and shared their views on the challenges and opportunities for advancing equity in transportation. Photo by Steve Goodman.
Panelists discussed equity initiatives underway in their organization and shared their views on the challenges and opportunities for advancing equity in transportation. Photo by Steve Goodman.

Perspectives on Advancing Equity in Transportation Panel Discussion Recording

The program continued as Amanda Gendek, Manager, NJDOT Bureau of Research, announced several awards given in recognition of research, innovation and implementation efforts.  Below is a listing of the award winners presented at this year's showcase:

  • 2022 Outstanding University Student in Transportation Research Award – Xiao Chen, Rutgers University (Innovative Pothole Repair Materials and Techniques)
  • 2022 Research Implementation Award – Anil Agrawal, City College of CUNY (NJDOT UAS/Drone Procedures Manual and Best Practices for Use in New Jersey)
  • 2022 Best Poster Award – Ahmed Edrees, New Jersey Institute of Technology (Minimizing Total Cost of Work Zones on Two-Lane Roads with Managed Lanes)
  • 2022 NJDOT Build a Better Mousetrap Award (State Agency) – Gary Liedtka-Bizuga and Henry Jablonski, NJDOT, Sawcut Vertical Curb

The Sawcut Vertical Curb was recognized as an innovative response to a change in standards requiring existing curbing at guide rails to be reduced in height. The Sawcut Vertical Curb innovation saves time and money and increases safety and efficiency by obviating the need to pour new concrete curbing and allowing guide rail to remain in place during the process.  A short video about the Sawcut Vertical Curb innovation was presented when the BABM award was announced during the event.

Presentation of Awards

Accepting the Better Mousetrap Award, Gary Liedtka-Bizuga, Roadway Design Group 1, with Acting Assistant Commissioner Parth Oza, Bureau of Research Manager, Amanda Gendek, and Assistant Commissioner Michael Russo. Not shown here: Henry Jablonski, Region Central Construction. Photo by Steve Goodman.
Best Poster Award Recipient, Ahmed Edrees, New Jersey Institute of Technology, Minimizing Total Cost of Work Zones on Two-Lane Roads with Managed Lanes. Photo by Steve Goodman.
2022 Outstanding University Student in Transportation Research Award, Xiao Chen, Rutgers University, Innovative Pothole Repair Materials and Techniques. Photo by Steve Goodman.
2022 Outstanding University Student in Transportation Research Award, Xiao Chen, Rutgers University, Innovative Pothole Repair Materials and Techniques. Photo by Steve Goodman.
2022 NJDOT Research Implementation Award, Anil Agrawal, City College of CUNY, NJDOT UAS/Drone Procedures Manual and Best Practices for Use in New Jersey. Photo by Steve Goodman.
2022 NJDOT Research Implementation Award, Anil Agrawal, City College of CUNY, NJDOT UAS/Drone Procedures Manual and Best Practices for Use in New Jersey. Photo by Steve Goodman.

AFTERNOON 

In the afternoon, concurrent break-out sessions for research presentations focused on the topics of Equity & Mobility, Infrastructure, and Safety in Transportation, and for the presentation of posters from students and researchers at New Jersey’s colleges and universities describing their methods and findings on ongoing and recently completed research and responding to questions by attendees.

Equity & Mobility Session Recording

Infrastructure Session Recording

Safety in Transportation Session Recording

 


Equity and Mobility Presentations

Peter J. Jin, Rutgers University-CAIT, Real-Time Traffic Signal System Performance Measure Phase II  LINK

Zijia Zhong, New Jersey Institute of Technology, Assessing High-Resolution Connected Vehicle Data for TSM&O Applications  LINK

Hannah Younes, Rutgers University-VTC, Factors Influencing the Fatality of Pedestrian and Bicyclist Involved Crashes in New Jersey  LINK

 


Infrastructure Presentations

Seyed Masoud Shirkhorshidi, New Jersey Institute of Technology, Corrosion Performance of Ultra-High Performance Concrete in Uncracked and Cracked Beams  LINK

Rojyar Barhemat, Soroush Mahjoub, Victor C. Li and Yi Bao, Stevens Institute of Technology  LINK

Ashith Padinhar and Marath Purakkal, Rowan CREATES, Developing Electrically-Heated Flexible Pavement for Self-Deicing Application LINK

 


Safety Presentations

Branislav Dimitrijevic, New Jersey Institute of Technology, Development and Evaluation of a Pedestrian Crossing Alert System Using 2-Channel LiDAR Sensor LINK

Anahita Kakhani, Rowan University, Emerging Countermeasures for Pedestrian Safety: A Review of State of Art and Recent Advances  LINK

Sam Rosenthal, Rutgers University, Complete and Green Streets: Effective Public Engagement Practics and Resouces to Promote Safety and Advance Equity  LINK

 


2022 Poster Presentations

Decision Aided Cost and Construction Time Estimates for the Gateway Tunnel Project - Ehsan Mehryaar, New Jersey Institute of Technology

Recommendations for Improving NJDOT Specifications for Cold In-Place Recycling - Ahmed Saidi, Rowan University

Minimizing Total Cost of Work Zones on Two-Lane Roads with Managed Lanes - Ahmed Edrees, New Jersey Institute of Technology

Simulating Corrosion Induced Damage in Recycled Aggregate Concrete Systems - Jin Fan, New Jersey Institute of Technology

A Review on Seat Belt Compliance of Drivers and Front Passengers: Data Collection, Analysis, and Countermeasures - Omar Al-Sheikh, Rowan University

Feasiblity Study of Shared Mobility Programs as a First/Last-Mile Solution in Underserved Communities: A Case Study in Camden City, NJ - Ruqaya Alfaris, Rowan University

Zero-Emission Bus Fleet: A Review of State Practices, Recent Developments, and Future Directions - Zahra Vafakhah, Rowan University

How Distraction Triggers Speeding: An Observational Case Study in New Jersey - Ahmed Sajid Hasan, Rowan University

Use of 100% RAP for Repair Purposes - Dr. Faisal Kabir, Rowan University

Three-Dimensional Finite Element Modeling of Cold In-Place Recycled Asphalt Sections in Accelerated Pavement Testing - Chenchen Huang, Cheng Zhu, Yusuf Mehta & Daniel Offenbacker, Rowan University

Assessment of the Impact of Binder Grade on the Laboratory Performance of Fiber-Reinforced Asphalt Mixtures - Ali Reza Khan, Ayman Ali, Yusuf Mehta, Rowan University

A Framework for Proactive Safety Evaluation of Intersection Using Surrogate Safety Measures and Non-Compliance Behavior - Deep Patel, Rowan University

 


Michael Russo
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Michael Russo
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The Research Showcase was organized by the NJDOT Bureau of Research in partnership with the Rutgers Center for Advanced Infrastructure and Transportation (CAIT) and the Rutgers Alan M. Voorhees Transportation Center. The 24th Annual NJDOT Research Showcase was co-sponsored by the Federal Highway Administration.

Share Your Ideas on the NJ Transportation Research Ideas Portal!

The New Jersey Department of Transportation’s (NJDOT) Bureau of Research invites you to share your ideas on the NJ Transportation Research Ideas Portal.

We are asking NJDOT’s research customers and other transportation stakeholders to propose research ideas for the NJDOT Research Program. Join us in finding workable solutions to problems that affect the safety, accessibility, and mobility of New Jersey’s residents, workers, visitors and businesses.

REGISTER TO PARTICIPATE.  Once you are registered, you may submit ideas at any time.  If you registered previously, you should not need to register again.  Click on the “+” button at the top of the page to register.

HOW DO I SUBMIT AN IDEA?  Only registered participants can log in to submit a new idea or vote on other ideas to show your support. Register at the NJ Transportation Research Ideas here:  https://njdottechtransfer.ideascale.com/

MORE INFO.  Our Welcome and FAQs page offers more information.

NEXT ROUND OF RESEARCH.  Submit your research ideas no later than December 31, 2022 for the next round of research RFPs. The NJDOT Research Oversight Committee (ROC) will prioritize research ideas after this date, and high priority research needs will be posted for proposals.

Questions about how to register?
Email: ideas@njdottechtransfer.net

For more information about NJDOT Bureau of Research, visit our website: https://www.state.nj.us/transportation/business/research/

Or contact us:  Bureau.Research@dot.nj.gov or (609) 963-2242

Research Spotlight: Calibration and Development of Safety Performance Functions for New Jersey

In 2019, a team of researchers from New York University and Rutgers University examined ways to calibrate and develop Safety Performance Functions (SPFs) to be utilized specifically to address conditions on New Jersey roadways. SPFs are crash prediction models or mathematical functions informed by data on road design. These data include, but are not limited to, lane and shoulder widths, the radius of the curves, and the presence of traffic control devices and turn lanes. With these data, SPFs help those tasked with road design and improvement to build roads and implement upgrades that maximize safety.

The Highway Safety Manual (HSM) presents SPFs developed using historic crash data collected from several states over several years at sites of the same facility type. These SPFs data cannot be transferred to other locations because of expected differences in environment and geographic characteristics, crash reporting policies and even local road regulations. To help SPFs better reflect local conditions and observed data, one of two strategies is usually undertaken to fine-tune SPFs:  calibrating the SPFs provided in the HSM so as to fully leverage these data or developing location-specific SPFs regardless of the predictive modeling framework included in the HSM.

The research team, led by Dr. Kaan Ozbay (of NYU’s Tandon School of Engineering), chose to pursue both of these strategies. The research report, Calibration/Development of Safety Performance Functions for New Jersey, can be found here. A webinar highlighting the research and findings can be found here.  A monograph, supported by the NJDOT funded study and partially by C2SMART, a Tier 1 UTC led by NYU and funded by the USDOT, was also recently published and can be found here.

C2SMART Webinar highlighted the research methods, findings, challenges and technology transfer efforts of the NYU-Rutgers team for this NJDOT funded research project.

SPFs can be utilized at several levels. At the network level, researchers and engineers use SPFs to identify locations with promise for improvement. SPFs can be used to predict how safety treatments will affect the likelihood of crashes based on traffic volume and facility type. SPFs can be used to influence project level design by showing the average predicted crash frequency for an existing road design, for alternate designs, and for brand-new roads.

SPFs also can be used to evaluate different engineering treatments. In this case, engineers and researchers return to a site where a safety countermeasure has been installed to collect and analyze data to see how the change has affected crash frequency. They examine before and after conditions and measure if the prediction made using the SPF was accurate or needs improvement (Srinivasan & Bauer, 2013). In the end, SPFs are only as good as the data used in their development.

NJDOT and the NYU-Rutgers team set out to calibrate SPFs using New Jersey’s roadway features, traffic volumes and crash data, and if necessary, to create new SPFs that reflect conditions in the state. The facility types considered for this research project included segments and intersections of rural two-lane two-way, rural multilane, and urban and suburban roads. In examining these datasets, the researchers identified areas where data processing improvements could be made to enhance the quality or efficiency in use of the data in addition to pursuing the stated goal of developing New Jersey-specific SPFs.

For example, utilizing the data provided by NJDOT, the research team developed methods for processing a Roadway Features Database of different kinds of road facilities. The researchers utilized the Straight Line Diagrams (SLD) database, which offers extensive information about the tens of thousands of miles of roadways in New Jersey, but observed issues and errors in the SLD database that required corrections. For example, the research team utilized Google Maps and Google Street View to conduct a manual data extraction process to verify information in the SLD database (e.g., confirm whether an intersection was an overpass, number of lanes, directionality) and extract missing variables, such as the number of left and right turn lanes at intersections, lighting conditions, and signalization needed for the analysis.

The research team using Google Street View to identify missing data points.

The research team also needed to develop programming code to correctly identify the type and location of intersections and effectively work with available data. The team developed a novel “clustering-based approach” to address the absence of horizontal curvature data using GIS centerline maps.

Utilizing Google Maps (Left) and the state’s Straight Line Database (Right), researchers were able to identify missing paths in the database that contributed to inconsistent data.

Police reports of crashes often have missing geographic identifiers which complicates analytical work such as whether crashes were intersection-related. In NJ, police are equipped with GPS devices to record crash coordinates but this crash information is somewhat low in the raw crash databases before post-processing by NJDOT. The researchers employed corrective methods and drew upon other NJ GIS maps to provide missing locations (e.g., Standard Route Identification or milepost).

The processing challenges for roadway features, traffic volumes and crashes encountered by the research team suggest the types of steps that can be taken to standardize and streamline data collection and processing to secure better inputs for future SPF updates. Novel data extraction methods will be needed to minimize labor time and improve accuracy of data; accurate crash data is integral to employing these methods.

The research team modified the spreadsheets developed by the HSM and used by the NJDOT staff. The calculated calibration factors and the developed SPFs are embedded in these spreadsheets. The users can now select whether to use the HSM SPFs with the calculated calibration factors or the New Jersey-specific SPF in their analyses

The researchers’ data processing and calibration efforts sought to ensure that the predictive models reflect New Jersey road conditions that are not directly reflected in the Highway Safety Manual. The adoption of this data-driven approach can make it possible to capture information about localized conditions but significant expertise is required to carry out calibration and development analyses. With more research—and improved data collection processes over time —the calibration and development of SPFs holds promise for helping New Jersey improve road safety.


Resources

Bartin, B., Ozbay, K., & Xu, C. (2022). Safety Performance Functions for Two-Lane Urban Arterial Segments. Retrieved from https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4175945

C2SMART. (2020, September 23). Webinar: Bekir Bartin, Calibration and Development of Safety Performance Functions for New Jersey . Retrieved from YouTube: https://youtu.be/IRalyvjDaFM

Ozbay, K., Nassif, H., Bartin, B., Xu, C., & Bhattacharyya, A. (2019). Calibration/Development of Safety Performance Functions for New Jersey [Final Report]. New Jersey Department of Transportation Bureau of Research. Retrieved from https://www.njdottechtransfer.net/wp-content/uploads/2020/07/FHWA-NJ-2019-007.pdf

Ozbay, K., Nassif, H., Bartin, B., Xu, C., & Bhattacharyya, A. (2019). Calibration/Development of Safety Performance Functions for New Jersey [Tech Brief]. Rutgers University. Department of Civil & Environmental Engineering; New York University. Tandon School of Engineering. Retrieved from https://www.njdottechtransfer.net/wp-content/uploads/2020/07/FHWA-NJ-2019-007-TB.pdf

Srinivasan, R., & Bauer, K. M. (2013). Safety Performance Function Development Guide: Developing Jurisdiction-Specific SPFs. The University of North Carolina, Highway Safety Research Center. Retrieved from https://rosap.ntl.bts.gov/view/dot/49505

NJDOT Tech Talk! Webinar – Research Showcase: Lunchtime Edition 2022

On April 21, 2022, the NJDOT Bureau of Research hosted a Lunchtime Tech Talk! webinar, “Research Showcase: Lunchtime Edition!”. The event featured three important research studies that NJDOT was not able to include in the NJDOT Research Showcase virtual event held last October. The Showcase serves as an opportunity for the New Jersey transportation community to learn about the broad scope of academic research initiatives underway in New Jersey.

The three research studies focused on evaluation and testing of the performance and durability of materials and pavement for use in transportation infrastructure. After each presentation, webinar participants had an opportunity to pose questions to the presenter.


Evaluating the Potential of Using Foamed Concrete as the Insulation Layer for Pavements in Cold Regions. Cheng Zhu, PhD, PE, Assistant Professor, Rowan University, Center for Research and Education in Advanced Transportation Engineering Systems (CREATES)

In cold-weather areas, water freezes and thaws in the subgrade layer of the soil and causes weak zones in the subgrade that affect surface layer performance. These weaknesses appear as pavement surface distress and cracking. To protect the subgrade, insulating material is used.

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Extruded polystyrene (XPS) boards are commonly used as insulation but face deterioration over time with water infiltration, and installation is time-consuming and labor-intensive. This study looked at the potential for using foamed concrete as an alternative material. The study also looked at the methodology of selecting optimum parameters that balance mechanical strength and insulating effect. When density is low, more air bubbles provide more insulation, but more density gives higher mechanical strength.

Some of the results found through laboratory testing and large-scale testing using a soil box, include: foamed concrete with higher density has a higher compressive strength, thermal conductivity, and a lower porosity; to ensure the subgrade layer remains unfrozen, there is a minimum insulation thickness needed for a foamed concrete layer; increasing the depth of the insulation layer will achieve a better mechanical performance, while also increasing the frozen depth; and using a foamed concrete with a higher density results in a better mechanical performance.

Several questions were posed to Dr. Cheng after his presentation:

Q. What is the estimated design life with foamed concrete?
A. We did not check the timeframe of the pavement structure. We are currently working on lab tests to study the real traffic load on the pavement structure. A simulation could also be used.  This is something that we are currently working on.

Q. Were you able to find an optimal thickness and depth combination in this research?
A. We have some recommendations for the specific material used in this study. We have a design table that we can share for the foam concrete material but was not included in this presentation. We did a comparison among several insulation materials including foamed concrete, tire chips, foamed glass aggregates, and XPS board.

Q. Was the insulation box used to create the sample box replicated in the real life soil scenario?
A. We used XPS board around the sides to minimize heat transfer and to ensure heat transfer process in this test is vertical. In reality, the heat transfer in pavement is in the vertical direction.


Development of High Friction Surface Treatment Pre-screening Protocols and an Alternative Friction Application. Thomas Bennert, PhD, Rutgers University, Center for Advanced Infrastructure and Transportation (CAIT) Associate Research Professor

The use of HFST can improve surface friction in road pavements around curves to reduce lane departure crashes or on steep declines to improve braking. With HFST, hard angular stone is glued to the pavement surface in less than a ½ inch application. The aggregate of choice, calcined bauxite, is applied using epoxy. HFST must be applied to pavements in “good” or better condition (i.e. with no cracking or rutting).

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There can be situations where pavement appears to be in good condition, but is not a good candidate for HFST. In 2018, in studies on two county roads, overlays showed signs of premature deterioration, probably due to previously undetected issues. It was determined that a prescreening protocol was needed to determine substrate conditions before HFST is applied. The study developed an effective prescreening tool that assesses the compatibility of asphalt and epoxy. Field core samples would be used to evaluate pull-off strength and relative asphalt binder properties.

The study also explored High Friction Chip Seal as an alternative to HFST. In a case study, an asphalt-based binding system was shown to be more compatible with the pavement than epoxy resin. Aggregate from local sources proved to be an acceptable substitute and less expensive than bauxite.

Following the presentation, Dr. Bennert responded to questions asked through the chat feature:

Q. What is the life expectancy of HFST? Is it suitable for places with higher traffic volumes?
A. If a road carries high traffic volumes, it is probably designed without horizontal curves and steep declines that might require quick braking. Some areas in Pennsylvania and lower volume highways have used this application. Pavement life expectancy is debatable but generally depends more on the level of traffic volume than years in place. At around a million passes, pavement starts to show raveling, in part due to the effects of UV on epoxy, but aggregate also debonds. Applications can lose friction quickly, an aspect that we are concerned with for its safety implications as well.

Q. Is there any difference in the noise with HFST?
A. In applications using aggregates that point upwards, there is a slight increase in noise at the tire-pavement interface, similar to noise resulting from other microsurface applications in place around the state.

Q. Anything similar to high friction chip seal in use elsewhere in the country?
A. No. We were one of the first to consider this particular application. We worked with the asphalt binder supplier and did some laboratory work and looked at durability. Chip seals have been used in other areas of the country in areas where friction is an issue, but chip seals have not been specifically designed as a friction treatment as this one is.


Influence of Cracking and Brine Concentration on Corrosion and Chloride Content. Aaron Strand is a Ph.D. Candidate in the John A. Reif, Jr. Department of Civil & Environmental Engineering at New Jersey Institute of Technology and recently defended his Ph.D. Dissertation successfully.

Throughout the U.S., agencies are using increasing amounts of salt and brine to counter road icing. Corrosion is an expensive problem for highway bridges. In reinforced concrete bridges, the primary cause of deterioration is chloride-induced corrosion. The focus of this study was the effect of surface-applied chlorides through road salting, typically using rock salt or brine. The research showed that the effect varies dependent on the condition of the bridge deck.

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The research explored whether current testing takes into consideration the amount of salt placed on the roads, salt placement cycles, and the current condition of the bridge deck. Chlorides can affect the bridge steel reinforcement through diffusion from the surface, and through cracks in the bridge deck. The variables explored were salt brine concentration and degree of cracking and their effect on the corrosion time of bridge decks. Testing was undertaken in the lab and from core samples from a large-scale bridge deck specimen.

Ongoing work based on this preliminary study includes testing of other concrete mixture designs, testing other rebar types, and developing a model for the amount of chloride content and corrosion current process. Looking at other concrete designs.

Mr. Strand answered several questions following his presentation:

Q. Among the cracked samples, did the higher brine solution show faster corrosion? What was the rate?
A. They all really showed corrosion immediately, at least in the macrocell test, but the rate was not shown. Going back to the total corrosion, six percent showed a quicker rate, but the other three passed the threshold at the half-year mark. There might be a decrease in the time to corrosion as the brine is increased, but it’s maybe not as much as would be expected from such an increase.

Q. Did you introduce temperature as a variable or do you see this as part of a future study?
A. This would be part of a future study. We did look at doing some type of freeze-thaw work on the concrete itself, but not as part of the brine cycling. As part of research into different mixture design, we would look into temperature’s role into the rate of ingress.

Q. How would you like to see your research findings used to inform bridge design, operations or maintenance in the future?
A. The testing we do shows how mixtures might perform together. For actual application-based work, we need to be more careful about the testing of the materials. For example, we know very little about how incorporating changes is in brine concentration might impact corrosion.

A recording of the webinar is available here.