UHPC for Bridge Preservation and Repair is a model innovation in the latest round of the FHWA’s Every Day Counts Program (EDC-6). UHPC is recognized as an innovative new material that can be used to extend the life of bridges.Its enhanced strength reduces the need for repairs, adding to the service life of a facility.
This Q&A article has been prepared following correspondence with Pranav Lathia, an NJDOT Supervising Engineer, Structural & RR Engineering Services, to learn more about current initiatives to test and deploy UHPC on the Garden State’s bridges. The Q&A correspondence has been edited for clarity.
Q. What is Ultra High Performance Concrete (UHPC), and why is it particularly useful for bridge preservation and repair (P&R)?
Ultra High Performance Concrete (UHPC) is a new class of concrete which contains extraordinary properties of durability and strength. UHPC is a cement based composite material, which consists of steel fiber reinforcement, cement, fine sand, and other admixtures. UHPC is a useful alternative for bridge repairs and preservation due to its long-term durability, which will minimize repairs to a specific structure over time.
Q. Why, in some cases, is UHPC a better application than traditional treatments?
Due to its chemical properties UHPC has a compressive strength of seven times that of regular concrete. Therefore, UHPC is mostly used for thin overlays, closure pours, link slabs, beam end repairs and joint headers.
Q. What are some advantages of UHPC?
UHPC overlays appear to have many ideal properties for deck surface, including superior bond strength, compressive strength, lower permeability, greater freeze-thaw damage resistance, good abrasion resistance, and rapid cure times, among others.
Q. What are some disadvantages to UHPC?
There are some disadvantages to UHPC. UHPC has higher material costs which has to be a factor in the Department's decision process. A life-cycle cost analysis is appropriate for making a determination of whether it is a cost-effective alternative for the Department. Fresh UHPC does not bond well to hardened UHPC, thereforecareful consideration for joint construction is needed, including reinforced staging joints. There is also limited test data for construction materials to determine their ability to perform well with UHPC. In addition, the NJ construction workforce is not very familiar with the use of UHPC as an overlay.
Figure 1: It is imperative that contractors establish the proper amount of UHPC fluidity to maintain the bridge deck’s grade. Courtesy of NJDOT.
Q. When is UHPC perhaps not an appropriate solution?
UHPC would not be an appropriate solution for a full deck replacement, superstructure replacement, or total replacement.
Q. What are some examples of UHPC’s previous implementations?
Before our initiation of a pilot program, UHPC had only been used for ABC (closure pours) and pre-cast connections in New Jersey since 2014.
Q. How is NJDOT approaching the potential implementation of UHPC for bridge preservation and replacement (P&R)?
Currently NJDOT uses UHPC ABC (closure pours) for prefabricated superstructures. NJDOT has launched and implemented a UHPC Overlay Research Project in conjunction with the design engineering firm, WSP Solutions.
Q. Can you describe the how UHPC is applied in the pilot project for P&R?
In the pilot project, a 1.5” UHPC overlay has been applied to four NJDOT structures. The UHPC overlay was constructed on the bridge deck along with the reconstruction of deteriorated deck joints.
Q. What bridges were selected, and what was the rationale for their selection?
Four structures were chosen for the UHPC overlay pilot program and split into two separate contracts, Contract A (North) and Contract B (South):
I-295 NB & US 130 NB over Mantua Creek in West Deptford, Gloucester County
NJ 57 over Hances Brook in Mansfield, Warren County
I-280 WB over Newark Turnpike in Kearny, Hudson County
NJ 159 WB over Passaic River in Montville, Morris County
The selected bridges for the pilot program were in good condition to leverage the perceived long life-span of UHPC and not allow other factors to limit the potential service life. Eight candidate structures were fully evaluated and tested before the four structures were advanced. The bridges that were ultimately selected varied in their age, size and design. All the bridges had asphalt overlay.
Q. What were the evaluation criteria used for the selection of the pilots?
All structures included in the program were evaluated for suitability based on the structural evaluations, chloride content within the deck, feasible construction stages, traffic analysis results, and existing overlay depths. Chloride content was obtained from the concrete cores we had completed on each bridge deck.
Q. What best practices were learned from the pilot projects?
It was best to install the UHPC overlays in locations that UHPC would serve as the final riding surface. The Department felt that an UHPC overlay should be constructed on structures which had an existing asphalt overlay. A thinner overlay could have been provided to cut material costs. Using a pan mixer, the supplier had the ability to control the fluidity of the UHPC, which is extremely important when dealing with extreme temperatures and high deflection/ movement structures. A flow test should continue to be required to verify the proper mixing and consistency of the UHPC overlay material.
Q. Were there any innovations from the implementation of the pilot projects?
A deeper overlay could be considered as a viable alternative for structures that need major deck rehabilitation or replacement.
Figure 2. An NJDOT UHPC treatment in the process of curing. Courtesy of NJDOT.
Q. How is data from the pilots being used to research further UHPC applications?
The data from the pilot program will be used to further the Department’s investigation in UHPC for applications other than just bridge deck overlays.
Q. What can be done to prepare industry and the workforce for UHPC as an overlay?
The implementation of UHPC affects the current workforce because it is a new material to be used in New Jersey. The current workforce does not have enough experience with UHPC’s properties which could make a repair more challenging. UHPC has only been used for closure pours in New Jersey. This knowledge gap could be solved by supplying the workforce with workshops, seminars, and suggested construction sequences, practices and equipment. A test slab should also be constructed to verify the proposed material and the contractor’s procedures.
Q. Are there needed actions to better educate NJDOT staff on its efficacy and potential uses?
Yes, training and peer exchange activities are valuable for further educating NJDOT staff on UHPC. Recently, we participated in a a two-day UHPC workshop (October 2021) with the U.S. Department of Transportation. The workshop providedparticipants with a greater understanding of what UHPC is, and explored solutions for using UHPC for bridge deck overlays, link slabs, and steel girder end repairs. Participants were given information on where to obtain guidance for implementing different types of UHPC preservation and repair strategies. The workshop also provided participants with the opportunity to discuss their UHPC implementation strategy, construction specifications, and design details with FHWA EDC-6 UHPC team members.
Figure 3. The final product, a UHPC overlay before asphalt paving. Courtesy of NJDOT.
Q. What does the future of UHPC look like in New Jersey?
The future of UHPC in New Jersey could consist of UHPC connection repairs, seismic retrofits, column repairs, concrete patching, shotcrete, steel girder strengthening, bridge deck overlays, and link slabs.
Q. In the current EDC-6 Round, the NJ STIC states that it is planning on performing an assessment of the UHPC pilot projects. When they are complete, how will they be assessed? Could you tell us more about the long-term testing program being developed to gather performance data in the assessment phase?
These are still works in progress. A long-term monitoring and testing program is being developed to gather performance data in the assessment phase. The scope of our current efforts includes further investigation and research, collection and evaluation of performance data, updating the standard specifications and conducting a life cycle cost analysis.
Q. Can you describe the objective(s) and/or provide any other status information about the long-term program goals?
A long-term goal for the department is to incorporate UHPC into our design manual, including for P&R.Eventually we could see UHPC incorporated with bridge deck overlays and concrete bridge repairs. There is currently no timeline on incorporating UHPC into the design manual. We anticipate revising the standard specifications, but there are no updates regarding the revision of the standard specifications for UHPC.
New Mexico Department of Transportation. (2010). Feasibility Analysis of Ultra High Performance Concrete for Prestressed Concrete Bridge Applications. New Mexico Department of Transportation. https://rosap.ntl.bts.gov/view/dot/24640
Early, effective, and continuous public involvement brings diverse viewpoints and values into the decision-making process. Transportation agencies can increase meaningful public involvement in planning and project development by integrating virtual tools into their overall public involvement approach. Public involvement tools and practices have expanded and shifted dramatically over the past decade due to changes in communications, technology, and lifestyles. Transportation professionals cannot expect the public to come to the transportation agency's events; practitioners must reach them in their everyday lives–online, at home, and in chosen gathering spaces.
RECENT WEBINARS. FHWA has been holding webinars on VPI topics:
Engaging Traditionally Underserved Communities describes considerations and strategies for engaging traditionally underserved populations when using VPI tools; a discussion of public meetings and NEPA-required public hearings for underserved communities; and includes a questions and answer session.
CASE STUDIES. FHWA has developed video case studies that highlight how transportation agencies are using virtual public involvement tools and techniques. This video series features short conversations with professionals involved in virtual public involvement efforts at their respective agencies. Agencies and topics featured in the Case Studies video are listed below.
WORKSHOPS. FHWA has been hosting in-person and online peer exchange workshops to provide a forum for sharing VPI strategies and practices. These peer exchanges bring experienced and less-experienced peers together to present and discuss their approaches to using specific VPI strategies. Various topics have touched upon project visualizations, online meetings, engaging traditionally underserved populations, and crowdsourcing approaches. The FHWA typically provides workshop summary reports, recordings, and other resources for each event.
The Intelligent Transportation Society of New Jersey (ITS-NJ) recognizes outstanding projects or programs that employ or advance ITS technologies. This year NJDOT’s “Weather Savvy Roads” system, also known as the Mobile RWIS effort, received its 2021 Outstanding Project Award.
NJDOT’s Weather Savvy Roads Program was recently recognized by the Intelligent Transportation Society of New Jersey
NJDOT’s Weather Savvy Roads (WSR) program started with NJDOT’s Mobility Division applying for and receiving NJ’s first federal Accelerated Innovation Deployment (AID) grant. The concept was to procure and install mobile RWIS devices and dash cameras in 23 DOT snow-fighting vehicles statewide to view real time conditions and guide decisions for allocation of resources during a winter event.
The team is comprised of staff from NJDOT Mobility, NJDOT Operations, the NJIT ITS Resource Center, and technical partners from Vaisala and EAI. NJIT created a web-based platform where users could view a statewide map and data from the RWIS devices and video from the CCTV6 in real time.
The WSR project was also designed to continue NJDOT’s investigation into cellular strength along NJDOT’s road network. This effort was first evaluated during NJ STIC Incentive grant funded program using iCone devices on SSP trucks. Utilizing a cellular router carrying FIRSTNET cellular capability, the technical team at NJIT is evaluating the strength of this first responder-only focused cellular system to see the various levels of signal strength. The project has shown tremendous benefits after just one winter season with staff across multiple levels of the Department utilizing the web platform to make better informed decisions about staffing and contractor use.
To learn more about the project, click on the NJ Innovative Initiatives, Weather Responsive Management Strategies page, or watch a presentation to the NJ STIC by Sal Cowan, Senior Director of Mobility at NJDOT about the equipment installation and web interface efforts taken for the pilot project.
Every Day Counts (EDC) is the Federal Highway Administration’s (FHWA’s) program to advance a culture of innovation in the transportation community in partnership with public and private stakeholders. Through this State-based effort, FHWA coordinates rapid deployment of proven strategies and technologies to shorten the project delivery process, enhance roadway safety, reduce traffic congestion, and integrate automation.
This report summarizes the June 2021 status of deployment for the seven innovations in the sixth round of EDC. The report is intended to be a resource for transportation stakeholders as they develop their deployment plans and to encourage innovation in managing highway project delivery to better serve the Nation.
The NJ State Transportation Innovation Council (NJ STIC) 3rd Quarter Meeting, held on September 15, 2021, featured presentations about the NJDOT Safety Voyager Tool and the NJ STIC Communications Plan, among other topics. The STIC Meeting Agenda had been distributed to the invitees prior to the meeting. Participants were invited to use the chat feature to offer comments or ask questions of the speakers during the online meeting.
Amanda Gendek, Manager of the NJDOT Bureau of Research greeted the meeting participants, followed by Asst. Commissioner Michael Russo who provided the Welcome and Opening Remarks.
FHWA EDC Innovation. Helene Roberts, Innovation Coordinator and Performance Manager for the FHWA NJ Office, noted that the first six-month progress report for the EDC initiatives and STIC incentive grant update reports were submitted, indicating few changes in the stage of implementation except for E-Ticketing and Digital As Builts. She shared a graphic of the EDC-6 deployment stage for each initiative illustrating the baseline assessment and goals for the two year period.
Ms. Roberts reported that NJDOT will pilot FHWA’s Let’s Go! Workshop which is designed to help in the formation of cohesive teams and plans to advance the EDC innovative initiatives. The workshops are scheduled for September 21st and 28th with a focus on the Strategic Workforce Development team, and the E-Construction team that will address Digital As-Builts and 3D Project Delivery. FHWA resource specialists for these subject areas will be present to assist in instruction and coaching for the pilot workshop(s).
Core Innovation Area (CIA) Updates. The meeting continued with presentations from Core Innovative Area (CIA) leaders who provided updates of the status of EDC initiatives on the topics of Safety, Infrastructure Preservation, Mobility and Operations, and Organizational Improvement and Support
Featured Presentations.
Peter Brzostowski, NJDOT Bureau of Transportation Data & Support shared an instructive video presentation that demonstrated several major features of the Safety Voyager tool which was followed by a questions and answer session. Safety Voyager is based on the NJTR-1 traffic enforcement crash reports. The tool provides information on crash incidents at specific intersections and corridors. Mr. Brzostowski walked through several scenarios to explore the various queries that can be made, for example, by weather-related events, years, type of crashes, and location, among others, and the use of modules that explore topics such as sun glare, weather, and crashes involving pedestrians and bicyclists. The tool includes an equity layer based on census data.
In response to a question, Mr. Brzostowski noted that employees of state government agencies, MPOs, and anyone working on a government project at any level can request access to Safety Voyager. Mike Russo added that the team had received input and feedback from various sources, and have been able to customize the tool to respond to primary customer needs. Expansion of the tool’s functionality continues.
David Aimen, Rutgers-Voorhees Transportation Center, presented on the NJ STIC Communications Plan, noting that the development of the Plan was funded in part by a STIC incentive grant and prepared on behalf of the NJDOT Bureau of Research – the administrative lead for the management of NJ STIC. The Plan seeks to improve the NJ STIC’s effectiveness through continuing communications and engagement with STIC stakeholders. The Plan increases awareness of the FHWA Every Day Counts Program and NJ STIC by identifying a toolbox of communication tools, methods and strategies that will be used to document performance, capture and share information on innovative initiatives, and promote implementation of these initiatives throughout the State. The Plan is posted on the NJ STIC section of the Technology Transfer website here.
Following the presentation, Amanda Gendek and Helene Roberts conducted an interactive exercise with attendees to help identify innovative practices that could be featured at future NJ STIC meetings, in future communications and/or other technology transfer activities. The interactive polling exercise solicited suggestions from attendees on innovations that have been advanced by organizations and provide useful lessons learned for others, innovations that should be more widely shared with the STIC and others, and topics for innovative case study videos. The exercise also solicited feedback on continuing training needs for specific EDC-6 initiatives.
Reminders and Updates.
Amanda Gendek closed the meeting with reminders about several resources that highlight the NJ STIC and other innovation topics funded through research and technology transfer activities, including:
The FHWA is promoting the deployment of Digital As-Builts (DABs) in Round 6 of the Every Day Counts (EDC-6) Program. FHWA defines DABs as an accumulation of the data used during digital project delivery that provides a living record of built infrastructure for agencies’ future business needs. The latest FHWA Innovator, September/October, Issue 86, features a section on e-Ticketing and Digital As Builts that briefly defines the innovation and its benefits along with a short video of digital delivery efforts at Utah DOT.
During EDC-6, the NJ STIC has set forward goals for advancing Digital As-Builts, assessing the current stage of innovation as “development” and setting forward some near-term capacity-building actions.
This article reports on a brief Digital As-Builts Literature Scan and provides references to a select bibliography of research reports, strategic plans and other resource documents that may warrant closer inspection for innovation teams. The literature scan identifies some key definitions, benefits, emerging practices, recurring challenges and possible lessons when taking steps toward deployment of DABs.
Digital As-Builts Literature Scan
Introduction
A Digital As-Built (DAB) innovates by transferring what are typically 2D, paper records into digital, three-dimensional (3D) datafiles that can be regularly updated and shared with stakeholders throughout a project’s life cycle. This information becomes invaluable in the asset management and operations phase, in which it is crucial for agencies to have the most current, comprehensive data covering their facility’s construction. DABs can also be referred to as digital twins, intricate computerized copies of a road or bridge that simulate real-time conditions, allowing for predictive maintenance and more cost-effective mitigation projects.
Across the country, state departments of transportation (state DOTs) are beginning to adopt DABs requirements for future road and bridge projects. The Pennsylvania Department of Transportation (PennDOT), for instance, has established ambitious agency goals that by 2035, all agency projects will be bid upon using 3D models—which will be updated throughout the project’s development through completion, and then stored in a centralized database (PennDOT, 2020).
While industry standard software and practices are still emerging, the research, experiences, and challenges from DOTs nationwide can assist in the identification of promising practices and planning the transition to DABs.
Benefits of Digital As-Builts
Digital As-Builts are digitized, detailed records of completed construction projects. These could encapsulate roadways, bridges, barriers, berms, and any other facilities. What is revolutionary about DABs is their capacity to be used as digital twins, sophisticated mock-ups of the actual structure that enable agencies to streamline maintenance and improvement projects. DABs are simple to store and distribute, reducing the time and material costs from producing traditional 2D as-builts. Created using Computer Aided Drafting and Design (CADD) software, and updated with real-world readings, such as laser-based LiDAR, DABs are versatile and, increasingly, trustworthy records.
DABs were selected as part of the FHWA’s EDC-6, featured for their advances in safety, time savings, and quality (FHWA, 2021). In addition to providing high quality records that can optimize maintenance and asset management, DABs can streamline the project development process by easily showing decision makers the location of existing infrastructure. The safety benefits come, in part, from shorter work interruptions of regular traffic flows.
DABs offer the capability to reliably retain information throughout the project process, as data is handed over from one department agency to another. A UC-Davis report, conducted on behalf of the California Department of Transportation (Caltrans), suggests that DABs can reduce the risk of lost information considerably (Advanced Highway Maintenance and Construction Technology Research Center, 2020). Another report, prepared for the Kentucky Transportation Cabinet (KYTC) by University of Kentucky researchers, found that digital documentation could significantly build trust in as-built records. In 2018, KYTC spent $217,000 on new forensic investigations because handmade, paper as-builts were deemed untrustworthy (Kentucky Transportation Center, 2019). But DABs, especially when well-updated and held to high standards of detail, can reduce the need for new surveys and ultimately lower costs.
DABs feed into an integrated workflow in which completed facility information is readily accessible for asset management and maintenance. This process is an element of Civil Integrated Management (CIM), and involves the entire lifecycle of a facility.
Existing Practices
Though many aspects of life have been affected by increasing digitization, the as-built record-keeping process in state transportation remains rooted in the analog era. It was apparent, from the literature reviewed, that the majority of state transportation departments are still using 2D, paper as-builts for facility specifications.
When DABs were being used, they were as pilot projects to demonstrate their efficacy. Or, when a part of agency practice, as in the case of Caltrans, implementation was inconsistent and without sufficient coordination (AHMCTRC, 2020). Similarly, in Kentucky, some records were being stored digitally but without a designated central repository, or as hardcopies in a State Library and Archives warehouse for storage (KTC, 2019), offering little use for ongoing maintenance. States like Michigan and North Carolina, while looking to transition to digital records, were still working on their digital strategies and have yet to implement them as practice (FHWA, 2019).
Some states have recently established regulations requiring DABs, such as the Colorado Department of Transportation (CDOT), which updated the State Highway Utility Accommodation Code in 2021 calling for 3D subsurface models showing the location of utility lines in CDOT’s Right-of-Way (Colorado Department of Transportation, 2021). New York has established a 3D, 4D, and 5D requirement for certain megaprojects (such as the new Kosciuzko Bridge), that tie contractor payments to a continuously-updated model that is then revised with as-built information (FHWA, 2014). And Nevada, while requiring digital contract documents, has yet to add an as-built component. (Nevada Department of Transportation, 2021).
Many DOTs are being spurred to action by technological innovations and by prior EDC rounds (FHWA, 2015) and by the current FHWA’s EDC-6 e-Ticketing and Digital As-Builts initiative.
Emerging Practices
PennDOT appears at the leading edge in its development of a comprehensive DAB implementation plan, intending to adopt the digital delivery process as a department standard by 2025. For DABs, this involves a 5-year span spent developing standards and workflows for implementation. The planning process includes the functioning of various working groups for determining necessary infrastructure and modeling requirements, workspace needs, and training plans. Though PennDOT’s plan is still in progress, their Digital Delivery 2025 Strategic Plan offers a good example of a comprehensive, implementation document detailing steps the agency must take to make the transition to digital delivery (PennDOT, 2020).
Figure 1: Sample Digital Delivery Roadmap from PennDOT.
Agencies in other states are also piloting new standards. Many DOTs are planning to convert from paper records, and to capitalize on this transition by taking advantage of the new digital records in the asset management process.
The Utah Department of Transportation of Transportation (UDOT) has created a website describing the benefits of digital delivery, including the advantages of the use of Digital Twins (UDOT, 2021). UDOT’s site also contains sample deliverables packages for contractors, with technical specifications for roadways, drainage, and structures viewable in Bentley ProjectWise, and document management software used for DABs by several DOTs (e.g., Virginia, Washington, Kentucky, and others) (Virginia Department of Transportation, 2019).
Virginia is also working to establish new guidelines to support the Civil Integrated Management (CIM) process. The guidelines will set standards for Level of Detail (LOD) for 3D renderings, as some models can be inconsistent. Because they are intended to exist as exact records of the constructed facility, DABs are required to be the highest LOD (Level 400) (Virginia Department of Transportation, 2020).
Michigan and North Carolina are currently transitioning from 2D plan sheets to 3D models of contractual documents (FHWA, 2019). Both states plan to incorporate the records into asset and operations management over the project’s lifecycle.
NYSDOT, for a bridge reconstruction in the Catskill region, developed a 3D model for a contract document using Bentley iTwin Design Review software (CS Engineer Magazine, 2021). After the bridge is completed, the contractor is obligated to upload as-built information to the 3D model. This approach is being piloted in New York, but is not yet adopted practice.
In Minnesota, the state Department of Transportation (MnDOT), adopted special as-built requirements for certain regions in the state, starting in the Minneapolis-St. Paul Metropolitan area (FHWA, 2019). The agency also has a dedicated website with DAB specifications. For example, a barrier as-built report might include latitudinal and longitudinal X, Y, and Z coordinates, as well as a Plan ID referring back to the plan set.
Nearby, Iowa DOT has begun using geo-equipped devices from ESRI to capture vector and asset attribute data during the construction process (Iowa DOT Research, 2021). The geolocated data captures the location and geometry of facilities, and is then uploaded to a Microsoft SQL server. As opposed to developing a 3D model in the design process, and then updating it with as-built conditions, an after-the-fact approach captures three-dimensional as-built data outside of the Building Information Modeling (BIM) process.
Other states are exploring how they might apply these concepts to how they manage the planning, design, construction, and maintenance of their facilities. The literature resources reviewed made the benefits of DABs abundantly clear, and showed considerable progress being made, but they also identified challenges in the full-scale deployment of Digital As-Builts as standard practice.
Challenges
Several of the resources reviewed identified barriers for DOTs for implementing DABs. For Developing a Strategic Roadmap for Caltrans Implementation of Virtual Design Construction/Civil Integrated Management (2020), researchers surveyed Caltrans employees from various departments to learn more about the obstacles that the department faced. Similarly, University of Kentucky researchers surveyed Kentucky Transportation Cabinet (KYTC) staff, in Redefining Construction As-Built Plans to Meet Current Kentucky Transportation Cabinet Needs (2019). FHWA has also prepared reports on innovative digital records practices at various states that detail various challenges (FHWA, 2019).
These reports reveal some recurring themes on the challenges experienced by state DOTs that can be broken into two axes — Workflow and Workforce — as well as some solutions to surmount them.
Table 1: Examples of Workflow and Workforce Challenges and Solutions to DABs Implementation
Axes
Challenges
Solutions
Examples
Workflow
Inconsistent Implementation
Develop robust, time-tested workflows
PennDOT
Workflow
Siloization
Facilitate interdepartmental coordination on projects and data updates
Caltrans
Workflow
Compatibility
Extensively test software workflows for technical errors, such as incompatibility
PennDOT
Workflow
Standards
Create file, format, and procedural standards (i.e. designated Levels of Detail). Require compatible software infrastructure to support DABs
PennDOT, UDOT, VDOT, NDOT, CDOT
Workforce
Digital Competencies
Educate employees with ongoing trainings that ease into DAB process
PennDOT
Workforce
Compliance
Educate for and enforce DAB protocols
UDOT, MnDOT
For example, the Caltrans report made clear that the development of an agency-wide workflow was paramount. Without one, various divisions were inconsistent and ineffective at capturing, maintaining, and communicating about DABs. Caltrans Roadway Design and Structures Design divisions fell short in updating and sharing the existence of updates with one another (AHMCTRC, 2020).
Regarding particular software, files, and workstations, care must be taken in the workflow design process to ensure compatibility. In Caltrans case, the Roadway Design and Structures Design divisions were using incompatible 3D modeling software. Iowa DOT experienced a similar issue, in which 3D, geolocated models created using ESRI software were then unable to be meaningfully edited in Bentley MicroStation (Iowa DOT Research, 2021). In addition, Iowa DOT’s 3D models, designed as part of a BIM process for a bridge girder replacement project, could not be edited because of the file type. An audit of Kentucky’s Transportation Cabinet found that, though there was a central repository for digital records (Bentley’s ProjectWise), files were uploaded inconsistently (KTC, 2019). While NYSDOT had planned, during the construction of the new Kosciusko Bridge, to continuously update a 3D model to show newly built components, they experienced severe network capacity constraints that prevented them from doing so (FHWA, 2014). Upfront planning, interdepartmental collaboration and testing ensures that DABs potential is unleashed.
The second tier of challenges arise from issues with workforce adoption. An FHWA case study looking at digital record keeping at MnDOT highlights difficulty with securing buy-in from construction staff to comply with new DAB requirements (FHWA, 2019). The KYTC study singled out a lack of digital competencies from older employees as one barrier towards adopting these new technologies. Change is difficult to implement, but especially when staff have become accustomed to the same practice for decades.
Recommendations
For Workflow design, a considered and deliberative process is required. Agencies must convene working groups of stakeholders and learn about department-specific concerns and established processes. Several years may be required to design new DAB workflows that maximize the potential of the new technology, and ensure that the infrastructure is in place to support and encourage staff to follow these workflows.
PennDOT’s plan for implementing digital delivery is an instructive and thorough model document on the subject (PennDOT, 2020). The agency’s Digital Delivery Strategic Plan breaks tasks down into actionable steps, such as Task 2.3, Post Construction Process and Procedures Development, scheduled from Q2-Q3 of 2021, which will map out new requirements and a plan to realize the new processes. An agency wishing to avoid siloization would do well to consult the UC-Davis study that provides itemized, exact solutions.
Figure 2: Another visual representation of PennDOT’s Digital Delivery Roadmap.
Architects of the new DAB workflow should be careful to promote interdepartmental collaboration, as well as select compatible software that supports such a goal. Bentley Systems design, engineering, and review software—MicroStation, OpenRoads, and ProjectWise, principally—appear to be the most consistently used across the country (AHMCTRC, 2020). For determining a cohesive workflow, it is imperative that varying software have compatibility with one another—and that they are consistently used across the department.
For the issue of designated detail levels, both Minnesota and Virginia have developed tables with standards specifying when and where to make DABs as accurate as possible, such as whether to survey the constructed facility at a detail of one foot or one meter (FHWA, 2019). The overall objective of the department may help to guide the development process: how does the agency aim to utilize BIM technology? A representative DAB could help to dramatically increase the efficiency of future maintenance or upgrade projects, but only if the appropriate standards are first put in place.
The Workforce presents complementary challenges and solutions. A technology is only useful if it is appropriately deployed—part of the workflow design process should include consultation with staff on specific barriers they face in their daily adoption of the technology. What might be preventing them from doing so? What types of trainings are required to achieve core competencies? Interviewing staff stakeholders will also help to determine accountability measures that could be put in place, for both staff and contractors, to help ensure consistent compliance with new workflows (KTC, 2019).
Moving Forward
Digital As-Builts are a promising technological innovation that can reduce inefficiencies in the life cycle of a transportation facility. If appropriately deployed, DABs can maximize the value of a project, eliminating the need for new forensic investigations, and retaining information as it is handed off from one phase to the next. Many of the DOTs surveyed are considering and incorporating innovative practices into their DAB implementation. Both Caltrans and KYTC, for example, are studying the use of laser-based scanning technologies to develop geolocated 3D models post-construction. In the coming years, as DABs are adopted into practice, more case studies will become available for reference.
From the resources reviewed, it was apparent that Digital As-Builts are promising technology that can streamline record-keeping and save transportation agencies both time and money.
Federal Highway Administration (2021). e-Ticketing and Digital As-Builts. Federal Highway Administration. https://www.fhwa.dot.gov/innovation/everydaycounts/edc_6/eticketing.cfm
This article first appeared in the FHWA’s EDC News Weekly Newsletter of August 26th, 2021 and featured NJDOT’s application of high performance thin overlays (HPTO) as a pavement preservation tool.
Targeted Overlay Pavement Solutions
Last week, we discussed a case study involving bonded concrete overlays, part of the Targeted Overlay Pavement Solutions (TOPS) toolbox. This week, we’ll look at how New Jersey has used high performance thin overlays (HPTO) successfully as a pavement preservation tool.
Since 2015, NJDOT has used HPTO on more than 1,000 lane miles to seal pavement and improve ride quality. Benefits include short road closures reducing impact on traffic, and addition of approximately 10 years of service life. Timing of the application is crucial. A Rutgers University study found applying HPTO to pavements while they are still in “good” condition more than doubles the service life compared to applying the product to pavements in “fair” condition.
Contractors who construct NJDOT projects have not reported constructability issues or complaints about the mix. NJDOT believes including performance requirements for the mixture, understanding treatment selection and application timing, and requiring project engineers to approve specifications are key factors in the success of HPTO as a pavement preservation tool.
Based on this research and evaluation of projects to date, NJDOT considers HPTO a cost-effective solution that provides a safe, smooth, crack and rut resistant surface that extends the life of the pavement and causes minimal impact on the road users and environment during construction.
A Pedestrian Hybrid Beacon (PHB) is a signalized, pedestrian-activated device designed to increase crossing safety. A recent study conducted by the New Jersey Bicycle and Pedestrian Resource Center (BPRC), funded by NJDOT, examined the efficacy and public awareness of PHBs in New Jersey. The authors, researchers from Rowan and Rutgers universities, found a persistent need to better educate motorists and pedestrians in New Jersey on the PHB and its phases.
The five phases Pedestrian Hybrid Beacon’s (PHB) operations
Pedestrian Hybrid Beacons are one of FHWA’s seven Safe Transportation for Every Pedestrian (STEP) countermeasures, proven methods of reducing pedestrian collisions. STEP was promoted through multiple rounds of the FHWA’s Every Day Counts (EDC) Program. A PHB is typically placed to improve pedestrian safety at uncontrolled and mid-block crossings, in locations with high pedestrian demand and wide roadways. The treatment consists of two signal arms on each side, with pedestrian “push buttons” and a crosswalk. The PHB operates in five phases. In the first, the PHB’s signal is off. The second phase begins when a pedestrian activates it by pressing a button, prompting the signal to flash a yellow light. Then, for the third phase, the flashing transitions to a solid yellow light, communicating to drivers that they should prepare to stop. Then the light turns red, and, in the fourth phase, the pedestrian signal changes to “Walk.” After an interval, the fifth phase begins: the pedestrian signal displays a countdown timer, and the traffic signal flashes alternating red lights, telling drivers to stop and that they may proceed if the crosswalk is clear.
The study’s literature review found multiple examples of prior research demonstrating the efficacy of PHBs. In the case of Tucson, Arizona, where one of the first PHBs was deployed in the United States, one study found a 69 percent decrease in pedestrian-related crashes in the signal area. Another analysis in Tucson found a 97 percent yielding rate from drivers at PHB-equipped crossings. One of the chief findings from the literature review was that PHB signal evaluations were lacking in New Jersey. Thus, researchers aimed to more systematically analyze PHBs in the state.
The authors found ten implemented examples of PHBs throughout the state, from Bergen County to Atlantic County. For more in-depth research, they selected signals in three different community types (urban, suburban, and campus area), in Morristown, Medford, and New Brunswick, New Jersey, to undergo video analysis.
The five phases Pedestrian Hybrid Beacon’s (PHB) operations
One commonality observed in all three locations was an apparent confusion for motorists concerning the fifth phase, in which the signal flashes red, indicating that drivers should stop and then proceed with caution. In New Brunswick, 100 percent of observed motorists remained stopped, even after the intersection had been cleared. In Morristown, the vast majority of pedestrians (91.3%) failed to use the PHB during the morning period, and also failed to do so in the evening (83%). The authors attribute such behavior to the PHB timing being linked to two nearby traffic signals, contributing to extra delay after the crossing button has been pressed. When inconvenient, it seems, pedestrians may opt to cross on their own.
To better understand the familiarity of pedestrians and motorists in New Jersey with PHBs, the researchers designed an online survey that was sent to 79,567 randomly selected email addresses from 30 communities across the state. While respondents indicated some confusion as to how PHBs functioned, a plurality indicated that they would be very likely or somewhat likely to support implementation in their own community. A majority of respondents (85.9%) reported that they had never heard of PHBs, and later indicated that completing the short survey had increased their knowledge of the safety treatment, showing the potential benefit of more public education about their functionality.
The report concludes by stating that while PHBs are proven to be effective at increasing pedestrian crossing safety, a lack of public awareness on the part of both drivers and pedestrians currently limits the effectiveness of these devices. The researchers suggest updating the New Jersey Motor Vehicle Commission’s Driver’s Handbook to include the PHB, and to differentiate the flashing red signals at a PHB where the driver must yield and then proceed if the crosswalk is clear, from the flashing red signals at railroad crossings where the driver is required to stop and remain stopped. This addition could be complemented with a public education campaign to teach pedestrians and drivers about the intricacies of Pedestrian Hybrid Beacons.
The New Jersey Bicycle and Pedestrian Resource Center (BPRC) works to promote a safer and more accessible walking and bicycling environment in the state. The Center, located at the Alan M. Voorhees Transportation Center at Rutgers, is supported by NJDOT through funding from FHWA. Further information technical assistance, resources for Complete Streets, and current research is available on the BPRC’s website.
Unmanned Aerial Systems (UAS), or drones, were promoted by the Federal Highway Administration (FHWA) as one of the Every Day Counts Round 5 (EDC-5) innovations. In 2017, the NJDOT Bureau of Aeronautics applied for and received a NJ State Transportation Innovation Council (STIC) Incentive Program Funding grant to purchase equipment and provide training to evaluate the use of UAS for applications within NJDOT. Prior research had determined that this innovative technology could improve safety and efficiency and reduce costs.
The final report, Unmanned Aircraft System (UAS): Purchase and Training, describes the use of the STIC funding to assist in establishing the UAS program within the Bureau of Aeronautics. The report describes the training curriculum and two use cases — high mast inspection and traffic incident management — and offers lessons learned and best practices.
The STIC grant, in combination with two other grants, enabled the Bureau to advance UAS within NJDOT. The innovation is now considered institutionalized within the agency. A video, Drone Technology at NJDOT, highlights the efforts to launch and integrate UAS in NJDOT operations.
FHWA offers up to $100,000 to each STIC each year. You can find out more about the STIC Incentive Program here.
