Strategic Issues Facing Transportation, Volume 7: Preservation, Maintenance, and Renewal of Highway Infrastructure (2020)

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26 This chapter identifies and characterizes emerging practices that are considered applicable for use in PMR of highway infrastructure; some of which may be regarded as innovative applica­ tions. With continual improvement over the next 30 to 50 years, these practices could become operational practices in the day­to­day business of transportation agencies. Literature Review The research team reviewed transportation and non­transportation literature to identify emerging and innovative practices that are on the outer edge of plausibility (beyond what the current state­of­the­art makes possible). Three technical issue papers (on advanced materials, asset preservation, and aging infrastructure) were reviewed. These papers were prepared in sup­ port of the National Surface Transportation Policy and Revenue Study Commission (NSTPRC, 2007) to provide recommendations regarding the nation’s future transportation system. Advancements in construction materials (e.g., concrete, steel, fiber­reinforced polymers, aggre gates, and fills) and design approaches (e.g., long­life pavements) have the potential to improve durability, expedite construction, and reduce upfront labor requirements and ongoing maintenance costs. Advanced construction technologies (e.g., prefabrication and precasting of bridge elements) can produce similar benefits: reducing traffic and environmental impacts dur­ ing construction, improving work zone safety, improving quality, and reducing life­cycle costs. Project management and execution techniques, such as earlier­phase constructability reviews (during design), construction management and scheduling innovations to compress construc­ tion durations, proactive coordination, and innovative procurement and contracting methods, can also provide similar benefits. In addition, a greater focus on asset management approaches could result in reductions in PMR needs. The implications of aging infrastructure (highways, transit, rail, and waterways) on long­term preservation and reconstruction needs were also explored. The analysis points out that older infrastructure has a greater probability of being in a deteriorated condition, less likely to meet current design standards, and more likely to be functionally inadequate. Also, the large group of old infrastructure structures with similar age ranges would have large, relatively simultaneous replacement needs in the future and thus affect future investment needs. Such a situation could be attenuated through maintenance and rehabilitation actions that affect the useful life of the transportation assets. There is some argument suggesting that PMR practices can conceivably extend the useful service lives of highways and bridges to the point that age becomes effectively irrelevant. C H A P T E R 3 Emerging PMR Practice Identification and Characterization

Emerging PMR Practice Identification and Characterization 27 European Perspective A perspective on the future (2040) from the European Commission was developed under the New Road Construction Concepts project (FEHRL, 2008). The project envisioned future transportation infrastructure that was more “human,” green, reliable, and safe. This long­term vision of road infrastructure was overlaid with innovations in urban infrastructure, interurban infrastructure, and bridges. The report presents the following broadly defined aspects of future infrastructure (FEHRL, 2008): • More humanized infrastructure that is more multimodal, multifunctional, accommodating of multiple users, and designed with greater attention to human scale. • Greener infrastructure through technologies that reduce traffic impacts (noise, air, and water pollution); the reuse and recycling of road materials; low­energy construction and mainte­ nance techniques; advanced pavement materials; the incorporation of energy recovery tech­ nologies in road infrastructure; reduced winter maintenance chemical pollution; and road concepts that reduce or clean particulate production. • More reliable infrastructure through hindrance­free maintenance activities; processes that extend maintenance seasons with less traffic impacts and the use of lighter, more durable, pre­ fabricated materials for bridges; high performance materials and maintenance technologies; design features to temporarily increase capacity (e.g., temporary or flexible lane configura­ tions) or to accommodate new transport systems (e.g., bus rapid transit or BRT, road trains); and asset management tools such as self­diagnostic, real­time monitoring and inspection to optimize maintenance planning. • Safer and smarter infrastructure (design, communication, and monitoring) through improved road design, construction, and maintenance technologies that minimize traffic impacts, mate­ rials and construction features that support enhanced safety (e.g., light reflecting surfaces for nighttime use, soft curbing for pedestrian/bicyclists), detection and warning systems for unsafe conditions, automated vehicle technologies, improved traveler information and com­ munication, and in­vehicle monitoring and detection systems generating data to enhance safety, routing, and real­time road conditions. Potential Emerging PMR Practices Establishing the Need for Innovative PMR Practices Drivers, scenarios, and potential implications presented in Table 2 provide a starting point for identifying potential future PMR practices. Scenario lenses, either singly or in combination, lend themselves to the future PMR needs of the highway infrastructure. Table 3 lists the future needs derived for each driver category.

28 Strategic Issues Facing Transportation Table 3. Future PMR practice needs. Driver Category Future PMR Practice Needs Demographics, Economics, and Transportation Demand Ability to accommodate growing traffic, reduce traffic congestion and disruption, improve highway safety, and ensure system reliability Resilience and Security: Natural and Man-made Threats Ability to adapt to climate change impacts, manage assets and risks, and provide rapid response Stewardship: Natural Resources and Communities Need for sustainable and environmentally responsible strategies, materials and processes to reduce energy consumption, emissions, depletion of natural resources, community impacts, and environmental footprint Financial Resources: Sources, Priorities, and Effectiveness Need to explore newer funding strategies more rigorously and objectively define priorities and to maximize cost-effectiveness through improved operational efficiencies and performance of infrastructure assets Technology: Materials and Methods Need for improved materials and methods to extend the life expectancy and minimize life-cycle costs of assets Technology: Information and Analysis Need for improved technologies, tools, and algorithms to collect, manage, visualize, and interpret data Vehicle Characteristics and Operations Ability to accommodate emerging trends in vehicle technologies, characteristics and operations Institutional Changes and Choices Need to foster positive changes as well as adapt to evolving institutional arrangements, human resources, and customer expectations Identifying Candidate Emerging PMR Practices The research team adopted a three­step approach to identify candidate emerging PMR prac­ tices. First, the research team identified emerging practices and practice areas that are receiving widespread attention based on their knowledge and experience. In the second step, the research team reviewed those practices identified in the prior NCHRP 20­83(03) report (TTI, 2012). In the third step, the research team identified emerging PMR practices influenced by and correlated with each of the driver categories, corresponding scenarios, scenario elements, and their implica­ tions (scenario lenses). This effort resulted in a list of over 60 potential practices. Two taxonomies were then selected to depict and consider them in a logical manner. The classifications reflect both the “why” and the “what” associated with each potential emerging PMR practice. The “why” classification was labeled “Functional Purpose” and the “what” classification was labeled “Emerging PMR Practice Type.” The five functional purpose classification categories and the four emerging practice type classification categories are listed in Table 4.

Emerging PMR Practice Identification and Characterization 29 Table 4. Emerging PMR practice classification. Classification Type Categories Functional Purpose Sustainability: Energy, Environmental Safety, and Natural Resource Conservation Traffic Operations, Safety, and System Reliability Asset Longevity and Life-Cycle Management Procurement and Methods Information Capture Technologies, Management, and Systems Emerging PMR Practice Type Materials Tools Approaches (New) Technologies Candidate Emerging PMR Practices Table 5 lists the identified 60+ candidate emerging PMR practices. These practices are more aptly thought of, in many instances, as practice areas. They are organized following the taxono­ mies listed in Table 4, first according to Functional Purpose and then according to Practice Type. Table 5. Emerging PMR practices organized by functional purpose and practice type. Functional Purpose Emerging PMR Practice Description and Examples Practice Type Sustainability: Energy, Environmental Safety, and Natural Resource Conservation Energy regenerative or renewable material sources, such as plant or micro-organism-based biogeotechnical materials, e.g., algae, vegetable oil, pyrolysis-based or lignin-based bio asphalt or resins Materials Renewable energy-based or energy responsive material production, such as low energy asphalt mix production and cleaner cement production (e.g., solar thermal electrochemical production process) Materials Environmentally responsive materials, such as low greenhouse gas emitting cement, carbon capture in cement concrete, and “self-cleansing” photocatalytic concrete or carbon nanotubes in concrete, and low energy asphalt to improve air quality Materials Applications of green chemistry in roadway material production and construction to reduce adverse risks to human health and the environment, such as geopolymers in concrete, magnesium oxide cement, non-corrosive anti-icing products Materials Increased use of recycling, such as higher percent of virgin materials substitution with recycled materials, advanced in-place material rejuvenation systems and permeable, elastic pavement blocks utilizing waste polyurethane Materials New tools to evaluate the sustainability of transportation projects, such as environmental product declarations to account for life-cycle environmental impact of a product, sustainability evaluation and rating methods for underground construction. Tools ISO:14025-based environmental product declarations for sustainability evaluation Tools Natural resource recharging structures, such as permeable yet structurally adequate pavements and roadside managed aquifer recharging, to reduce precipitation run-off Approaches Urban roadway surfaces with high solar reflectance, such as light colored asphalt pavement surfaces, to reduce urban heat island effect Approaches (continued on next page)

30 Strategic Issues Facing Transportation Functional Purpose Emerging PMR Practice Description and Examples Practice Type Sustainability: Energy, Environmental Safety, and Natural Resource Conservation (continued) Advanced roadway and roadside noise mitigation systems, such as sound absorptive high strength concrete; solar power generating noise attenuators; weather resistant, visually appealing, vinyl- based transparent noise barrier screens; and noise reducing natural landscaping Approaches Urban “green” highways with landscaped deck ceilings Approaches Sustainable roadside landscapes with greater emphasis on native habitat that supports natural heritage, biodiversity, native vegetation, low-maintenance, xeriscaping, on-site composting, and natural fertilizers Approaches Road-based energy-harvesting technologies, such as piezoelectric generators, dynamic speed bumps, and solar energy convertors Technologies Renewable energy-based or energy responsive construction equipment, such as green paving trains using non-carbon, renewable fuels and battery-operated electrical vehicles Technologies Applications of geothermal energy, such as for deicing bridge decks Technologies Traffic Operations, Safety, and System Reliability Design, safety and maintenance standards for ancillary assets in automated vehicle pathways (e.g., specialty signs and markings) Tools Artificial intelligence applications in traffic operations (e,g., signalization, travel demand management and behavior analysis) and emergency response (e.g., intelligent emergency evacuation guidance) Tools Dedicated corridors for automated vehicles that require specialized maintenance, such as dedicated lanes for automated trucks, BRT, and automobile platoons. Approaches Multi-decked highways for traffic (including dedicated lanes for specific vehicle types) Approaches Smart roadway surfaces (with embedded dynamic traffic channelization and controls) Approaches Advanced transportation systems management and operations (TSMO) device and communications systems maintenance Approaches Probe-based (vehicle and/or sensor-based) connected vehicle applications to supply real-time asset inventory, health, condition, and performance data collection and reporting, such as real-time, probe- based smoothness and friction measurement Technologies Connected V2I technology providing communications between passing vehicles and roadside units Technologies Automated enforcement technologies for work zones Technologies Highway systems/managed motorways fitted with non-traditional, high value, ancillary structural assets, such as guardrails with alert sensors, and self-actuating impact attenuators and crash cushions Technologies Asset Longevity and Life-Cycle Management High performance materials for roadway structures with high strength and enhanced durability, including many variations of high performance steel, concrete, asphalt, aluminum, and plastics Materials Superior quality roadway surfaces, such as the use of abrasion resistant roadway materials, high friction mastics, surface protection laminates and texturing methods, e.g., prefabricated thin rollable pavement surface with epoxy resin and chippings on textile-reinforced concrete Materials Materials with crack healing properties, such as self-healing asphalt and self-healing bioconcrete, for improved mechanical properties and durability Materials Nanotechnology-based construction materials for improved mechanical properties and durability Materials Microbial geotechnology applications such as bioclogging and biocementation to improve mechanical and hydraulic properties of soils Materials Composites for reinforcement of roadway structures to improve mechanical properties, and durability, such as carbon and glass fiber reinforced polymers Materials Cost-effective solutions, such as lightweight fill for embankments (e.g., geofoam, low-density cementitious fill, and expanded shale) Materials (continued on next page) Table 5. Emerging PMR practices organized by functional purpose and practice type (continued).

Emerging PMR Practice Identification and Characterization 31 Functional Purpose Emerging PMR Practice Description and Examples Practice Type Asset Longevity and Life-Cycle Management (continued) Machine learning applications in developing more reliable, robust and data-driven decision support systems Tools Application of mechanistic perpetual/long-life concepts for roadway infrastructure in materials, design, construction practices, and management Approaches Predictive-proactive maintenance regime for roadway assets, e.g., reliability centered maintenance Approaches Applications of “Preservation First” approach integrated into asset life-cycle management Approaches Pre-stressed concrete slab technology for increased durability and better crack control Technologies Procurement and Methods Enterprise information systems for business process integration Tools Customer experience management (CXM) analytics in decision making Tools Decision support systems for roadway maintenance, such as summer and winter maintenance Tools Game and simulation-based workforce training solutions Tools Performance- and qualifications-based procurement for all phases of roadway project, including design, construction, maintenance and operations Approaches Outsourcing and privatization of PMR Approaches Newer revenue and financing models, such as crowdsourced funding Approaches Human resource innovations at workplace, such as intellectual property-based incentives, workforce performance management Approaches Newer warranty schemes, such as private–public partnership (P3) project warranties, to ensure quality Approaches Increased use of prefabrication, modular assembly, and offsite construction for improved construction productivity, quality, and work zone management Technologies Robotics in prefabrication, modular assembly, construction, maintenance and repair, for improved construction productivity, quality, and work zone management Technologies 3D printing of infrastructure components for faster construction maintenance and repair Technologies Advanced construction methods, such as large diameter tunneling and magnetic levitation technology for bridge/elevated deck heavy lift structural placement, to improve construction productivity, quality and work zone management Technologies Intelligent construction systems, machines and technologies for improved construction productivity and quality with real-time monitoring of material placement and compaction using electromagnetic technologies (e.g., infrared) Technologies New subsurface maintenance and repair technologies using polymer-based superabsorbent water blocking agents, regenerative polymers, and flexible robots made with silicone rubber and microfluidic channels for crack sealing/grouting that can wiggle itself through cracks Technologies Non-destructive testing for ancillary assets, e.g., linear polarization resistance devices, pulse repetition frequency, guided wave ultrasonic testing, asset condition imaging using electromagnetic technologies Technologies Table 5. Emerging PMR practices organized by functional purpose and practice type (continued).

32 Strategic Issues Facing Transportation Most Promising Emerging PMR Practices Screening Criteria The research team applied the following criteria to identify promising PMR practices for further consideration. • Responsive to Scenario Elements: Is the practice responsive to more than one of the scenario elements identified in Table 2? A rating scale of 1 to 5 was used with the values 1 and 5 indicat­ ing lowest and highest number of scenario elements, respectively, to which a specific practice was responsive. • Departure from Current Practice: Is the emerging practice new or significantly different from that in current use (i.e., representing advancement in performance and/or cost­ effectiveness)? Is the practice incremental or radical in relation to corresponding present day state of the practice? A rating scale of 1 to 4 was used to indicate whether the practice would be incre­ mental or radical. • Scale of Impact: How big of a difference does the emerging PMR practice make in the prepa­ ration for the future? A rating scale of 1 to 4 was used with the values 1 and 4 indicating lowest and most significant impact, respectively. • Plausibility: Is the selected emerging PMR practice within the outer limits of present­day plausibility and with a reasonable likelihood of feasibility and acceptance in the future? What is the likelihood of future deployment considering the following implementation factors? A rating scale of 1 to 4 was used with the values 1 and 4 indicating if a given emerging PMR practice is infeasible or feasible with no barriers, respectively, in the following categories. – Implementation requirements (e.g., training and standardization). – Existing regulations or standards. – Political or public acceptance. – Approval processes. – Inertia of existing processes and methods. – Availability of vendors or support base. Application of Screening Criteria The ranking approach was applied to the 60+ practices to identify the top 24 most promising practices. For a comparative evaluation of the candidate practices, rating scores of 1 to 5 (or 1 to 4) were assigned to each criteria to indicate their importance among the screening criteria. Weights totaling 100 were assigned to each evaluation factor to reflect their relative importance among all factors. The evaluation factors and their relative weights, and the evaluation criteria and their rating scores are listed in Table 6.

Emerging PMR Practice Identification and Characterization 33 Table 6. Evaluation criteria for candidate emerging PMR practices. Evaluation Factor Relative Weight Rating Scale Criteria Rating Score Responsive to Scenario Elements 40% Number of elements less than 5 Between 6 and 10 Between 11 and 15 Between 16 and 20 Number of elements greater than 20 1 2 3 4 5 Scale of Impact 30% Low impact Modest impact Moderate impact High impact 1/4 2/4 3/4 4/4 Departure from Current Practice 15% Incremental Next Generation Breakthrough Radical 1/4 2/4 3/4 4/4 Plausibility 15% Not Feasible Many Barriers Few Barriers No Barriers 1/4 2/4 3/4 4/4 The weighted scores were then calculated for each practice by multiplying its evaluation rat­ ing score with the corresponding weight. The 24 practice candidates with the highest weighted scores were selected as promising emerging PMR practices for further consideration; these are listed in Table 7.

34 Strategic Issues Facing Transportation Table 7. Promising emerging PMR practices. Emerging PMR Practice Type Emerging PMR Practices (or Practice Areas) Materials • Green Chemistry—PMR Applications • Hyper-Performance Materials Tools • Non-Destructive Testing for Ancillary Assets • Structural Health Monitoring • CXM Analytics • Machine Learning—Artificial Intelligence for Asset Management • Environmental Product Declarations • Integrated Building Information Modeling (iBIM) for Highways • Enterprise Information Systems—PMR Applications • Game/Simulation Workforce Training • Connected Vehicle Applications to Supply Real-time Conditions Information • Artificial Intelligence—PMR Traffic Management Applications Approaches • Predictive–Proactive Maintenance Regime for Roadway Assets • The “Internet of Things” (IoT)—PMR Applications • Self-Diagnosing/Reporting and Work Ordering • Perpetual/Long-Life Highway Infrastructure • Advanced TSMO Device and Communications Systems Maintenance • Connected V2I Technology Providing Communications Between Passing Vehicles and Roadside Units • Dedicated Corridors for Automated Vehicles • Automated Enforcement for Work Zones • Outsourcing and Privatization of PMR Technologies • 3D Printing of Infrastructure Components • Construction Robotics • Remote Sensing Systems—PMR Applications Characterization and Description of Emerging PMR Practices A brief narrative that characterizes each of the 24 promising emerging PMR practices is pro­ vided in Appendix B (available as part of NCHRP Web-Only Document 272); it includes the following: • A brief description. • Potential benefits from adoption. • Description of how the practice would transition from the current to future scenario(s). • Readiness for adoption over the long run considering future research, dependence on devel­ opments in non­transportation areas, and implementation and funding requirements. Summary tables for each of the eight driver categories are provided in Appendix C (available as part of NCHRP Web-Only Document 272). The tables show how each scenario lens is related to candidate emerging PMR practices.

Emerging PMR Practice Identification and Characterization 35 Outreach Process The research team held outreach sessions with transportation stakeholders to identify the most promising PMR practices and to seek input on how to organize guidance that will help agencies deal with these practices. The participants included (1) transportation agency senior leadership and officials from major cities and counties who will influence the receptivity to emerging practices as well as take action for change management in anticipation of potential new ways of doing business; (2) technical managers and discipline practitioners in the key areas (e.g., pavement managers or bridge engineers) who will put a tactical plan in place to deploy emerging PMR practices to enhance their ability to achieve performance goals; and (3) researchers and educators who will consider the emerging PMR practices as well as the broader practice areas to set research priorities and assist with creating a smarter, next­generation work force. The par­ ticipants included representatives from various disciplines, including infrastructure components (e.g., bridges, pavements, and other assets), material types, and field activities (e.g., preservation, maintenance, rehabilitation). Two outreach groups were formed: one composed of agency lead­ ers and the other composed of practitioners. Prior to the outreach sessions, the participants were debriefed on the specifics of the project, its objectives, research methodology, including drivers; future PMR needs; relevant PMR prac­ tice identification process; and a brief description of the promising emerging practices. The participants were then asked to evaluate 24 emerging PMR practices using three specific criteria (scale of impact, plausibility, and benefits) and place them into three categories reflecting their priority for inclusion in the guidance (must include, should include, and not urgent to include). 1) Scale of Impact a) How big a difference does the PMR practice make in the context of need for adopt­ ing it to tackle future PMR needs? b) Is it expected to impact multiple PMR disciplines? i) PMR disciplines considered in the research include pavement, structures, drainage and roadside, TSMO, CAVs, maintenance and construction equip­ ment, and information technology/data. c) Within those disciplines, is the practice wide­ranging in its impact or only focused on a particular circumstance or context? 2) Plausibility a) Is the PMR practice within the outer limits of present­day plausibility? b) Is there reasonable likelihood of feasibility and acceptance in the future? c) Does the practice face few or many barriers, and what is the likelihood of overcom­ ing them? d) What is the likelihood of future deployment of the PMR practice considering the following implementation factors? i) Need for additional implementation requirements, including training and standards. ii) Conflict with existing regulations or standards. iii) Lack of political or public acceptance. iv) Extended or problematic approval processes. v) Inertia of existing processes and methods. vi) Lack in presence of necessary vendor or support base.

36 Strategic Issues Facing Transportation 3) Benefits a) Are the benefits compelling in light of risks, challenges, and costs? b) Do the benefits accrue internal or external to the agency, or both (see benefits types listed in Table 9). c) Are there benefits from the PMR practice applied singly, and do they increase through synergies with other practices? Participants’ Ratings Eleven responses were provided by the participants. The number of responses in each category for each emerging PMR practice are listed in Table 8 and also presented in Figure 2. Table 8. Participants’ rating of including emerging PMR practices in guidance. Emerging PMR Practice Participant Rating Must Include Should Include Not Urgent to Include 1. Green Chemistry—PMR Applications 3 5 3 2. Hyper-Performance Materials 9 1 1 3. Non-Destructive Testing for Ancillary Assets 1 6 4 4. Structural Health Monitoring 6 3 2 5. CXM Analytics 4 3 4 6. Machine Learning—Artificial Intelligence for Asset Management 7 2 2 7. Environmental Product Declarations (EPDs) 2 5 4 8. Integrated Building Information Modeling (iBIM) for Highways 8 1 2 9. Enterprise Information Systems – PMR Applications 5 3 3 10. Game/Simulation Workforce Training 2 5 4 11. Connected Vehicle Applications to Supply Real-Time Conditions Information 7 3 1 12. Artificial Intelligence—PMR Traffic Management Applications 4 4 2 13. Predictive-Proactive Maintenance Regime for Roadway Assets 6 4 1 14. The IoT—PMR Applications 3 6 2 15. Self-Diagnosing/Reporting and Work Ordering 4 5 2 16. Perpetual/Long-Life Highway Infrastructure 7 4 0 17. Advanced TSMO Device and Communications Systems Maintenance 4 5 2 18. Connected V2I Technology Providing Communications Between Passing Vehicles and Roadside Units 9 1 1 19. Dedicated Corridors for Automated Vehicles 2 3 6 20. Automated Enforcement for Work Zones 7 1 3 21. Outsourcing and Privatization of PMR 2 3 6 22. 3D Printing of Infrastructure Components 1 7 3 23. Construction Robotics 4 7 0 24. Remote Sensing Systems—PMR Applications 7 3 1

Emerging PMR Practice Identification and Characterization 37 Suggested Emerging PMR Practices The 16 highest­ranked (most promising) emerging PMR practices were: • Hyper­Performance Materials • Connected V2I Technology Providing Communications between Passing Vehicles and Roadside Units • Perpetual/Long­Life Highway Infrastructure • Integrated Building Information Modeling (iBIM) for Highways • Connected Vehicle Applications to Supply Real­Time Conditions Information • Remote Sensing Systems – PMR Applications • Machine Learning – Artificial Intelligence for Asset Management • Predictive­Proactive Maintenance Regime for Roadway Assets • Automated Enforcement for Work Zones • Structural Health Monitoring • Construction Robotics • Enterprise Information Systems—PMR Applications • Self­Diagnosing/Reporting and Work Ordering • Advanced TSMO Device and Communications Systems Maintenance 0% 20% 40% 60% 80% 100% Hyper-Performance Materials CV to Infrastructure (V2I) Technology Perpetual/Long-Life Highway Infrastructure Integrated Building Information Modeling (iBIM) CV Applications to Supply Real-Time Conditions Information Remote Sensing Systems – PMR Applications Machine Learning – A.I. for Asset Management Predictive-Proactive Maintenance Regime for Roadway Assets Automated Enforcement for Work Zones Structural Health Monitoring Construction Robotics Enterprise Information Systems – PMR Applications Self-Diagnosing/Reporting and Work Ordering Advanced TSMO Device and Communications Systems Maintenance The Internet of Things (IoT) – PMR Applications Artificial Intelligence – PMR Traffic Management Customer Experience Management (CXM) Analytics Green Chemistry – PMR Applications Environmental Product Declarations (EPDs) Game/Simulation Workforce Training 3D Printing of Infrastructure Components Non-Destructive Testing for Ancillary Assets Dedicated Corridors for Automated Vehicles Outsourcing and Privatization of PMR Summary of Ratings of Emerging PMR Practices and Innovations Must Include Should Include Not Urgent to Include Figure 2. Participants’ rating of including emerging PMR practices in guidance (CV = connected vehicle).

38 Strategic Issues Facing Transportation • IoT—PMR Applications • Artificial Intelligence—PMR Traffic Management Applications The lowest­ranked 8 PMR practices (i.e., 17 to 24) were: • CXM Analytics • Green Chemistry—PMR Applications • EPDs • Game/Simulation Workforce Training • 3D Printing of Infrastructure Components • Non­Destructive Testing for Ancillary Assets • Dedicated Corridors for Automated Vehicles • Outsourcing and Privatization of PMR The 16 highest­ranked practices were used in preparing detailed guidance as part of the project. However, interested parties may consider all 24 PMR practices or the initial 60+ prac­ tices for further development.