03-Appendix C - Research Topics.DOCX

Appendix C – Research Topics

BROAD AGENCY ANNOUNCEMENT

Federal Highway Administration Office of Acquisition and Grants Management Research Initiatives in Support of Structural Engineering Programs Note: Concept papers may be submitted at any time, through the closing date of the research topic.

General Topics

Concrete Bridge Program

Steel Bridge Program

Load Rating Program

Seismic and Multi-Hazard Resilience Program

Bridge and Tunnel Security

Fiber Reinforced Polymer (FRP) Composite Technology

General Topic Topic: HIBS10-GT-001 Title: Innovative Practices to Educate Bridge Engineering Practitioners Most undergraduate structural engineering curricula do not fully prepare students for professional practice in bridge engineering. Bridge design firms are challenged to educate new engineers on topics that are beyond what is considered normal “on-the-job-training.” Further, the rapid pace of specifications and standards changes and software development, makes continuing education and training a significant and ongoing challenge. Design offices typically turn to seminars and workshops that offer a condensed format to fit a time constraint and usually provide little to no hands-on application exercises and interactive assignments. Further, the current generation of professionals have different learning preferences which have been influenced by the maturity of web-based information and tools such as massive open online courses (MOOC), videos, and other self-directed learning tools. This topic seeks innovative approaches to address both identification of education gaps and innovative education tools. The FHWA seeks solutions for this topic which address the following:

1. Research how the structural engineering college curriculums in the US are preparing engineers with the necessary skills and knowledge for the bridge engineering practice. Identify and prioritize bridge engineering continuing education gaps and develop education solutions for these gaps.

2. Research and identify innovative teaching platforms and media that can accommodate the needs, schedule, and learning preferences of a current practicing bridge designer.

3. Recommend needed college level courses and education platforms or processes that can effectively educate practitioners individually, locally, regionally, and nationally.

Concrete Bridge Program Topic: HIBS10-CB-001 Title: Bridge Post-Tensioning (PT) Laboratory Poor performance of multi-strand post-tensioning tendons for bridge applications can significantly reduce a structure’s service life, and impact strength and safety. The post-tensioning (PT) industry is ever changing to improve the performance of PT systems. This is achieved through the development of new / innovative technologies and enhanced installer and inspector training. This topic seeks to develop a business plan for a future Bridge PT Laboratory that will both train PT installers / inspectors and test promising PT technologies.

The PT Laboratory will implement PT installer and inspector training that will provide both lecture and “hands-on” training. In addition, this PT laboratory will have the capability to test and verify intended performance of promising PT technologies.

This topic seeks to develop a business plan for a future Bridge PT Laboratory. This business plan should address: Business Description, Marketing/Sales Strategy, Management/Staffing, Operations, Projections for Financial Performance, Funding Mechanism, Potential Facilities, Industry Engagement, and an Executive Management and Oversight Plan.

A significant part of this topic is to identify the needed infrastructure for the center. The center must have the capability to facilitate moderate scale multi-strand PT tendon installation and grouting operations in a real-world environment.

Topic: HIBS10-CB-002 Title: Post-Tensioning (PT) Tendon Force Assessment for Bridges Quantifying prestress forces for post-tensioned bridges during their service life, and identifying losses, is of great interest to the engineering community, to assure structural capacity and safety in such bridges. This information can be used by bridge owners to address developing issues for their bridges in a timely manner and allow for proactive vs. reactive resolutions. This topic seeks methodology, tools, and technologies intended for new construction that can provide accurate and readily obtainable prestress force data for PT tendons. These technologies must be past the proof of concept phase and be ready for implementation as part of routine bridge inspection. The proposed solution for this topic shall:

· Provide accurate data along the tendon length

· Be able to provide data for the bridges expected service life

· Not affect the performance of the PT tendon

· Minimally impact current tendon installation practices

· Applicable to both internal bonded PT and external un-bonded PT In addition, solutions shall include a research/testing plan to verify the performance of the technology.

Steel Bridge Program Topic: HIBS10-SB-001 Tittle: Material Innovations for Steel Bridge Members Innovative materials for structural steels are very important in advancing the engineering practice of modern steel bridges and improving physical performance. New and improved structural steels and steel components, by means of either chemistry, mill practice, or heat treatment, may provide higher yielding strength, better toughness, improved corrosion resistance, and more uniform quality. These innovations may significantly change the design, fabrication, maintenance, and may be more competitive in life-cycle costs. FHWA seeks solutions to advance the state of engineering knowledge and readiness, through research and development, testing and demonstration, and through close collaboration with owners, engineers, researchers, fabricators, and steel industry. The outcome is expected to lead to nationally applicable engineering guidance, standards, and specifications. The FHWA is interested in structural steel material innovations that may include, but are not limited to:

· Duplex Stainless-Steels (addressing issues with: weldability and WPS, hybrid design, fasteners, etc.)

· Heat-treated Components (addressing issues with: HPS plates and shapes, high strength bolts and anchor bolts, welding, coating, fatigue and fracture, tensile strength to yielding strength ratio -T/Y ratio, fabrication and construction, real bridge lessons, etc.)

· Alternative Weathering Steels (addressing issues with: aesthetics and durability, patina, change of steel alloy chemistry, deleterious effects to the steel mechanical, corrosion, and weldability properties, etc.)

Topic: HIBS10-SB-002 Tittle: Innovative Detailing and Fabrication for Steel Bridge Members Steel bridges often use details that have been carried over from legacy practices, along with associated fabrication techniques. These details and fabrication techniques have been proven generally successful through experience and trials and have provided consistency in design and efficiency in fabrication. Some of the details and legacy design rules are still very difficult to justify or explain even with modern refined analysis. Some legacy practices may be proven to be too conservative or unconservative. Some detailing techniques may be good for one application, but not so for another. Some detailing techniques may be labor intensive, and may be very difficult to inspect or maintain. Changes also come with the advancement in material and in shop practice, like welding process, quality control, and automation. Modern bridge design concepts may bring up new structural member types and systems, changing or eliminating some connections. New coating systems may introduce considerations different from traditional concepts. FHWA seeks innovative detailing and fabrication solutions, to advance the state of engineering knowledge and improve bridge performance.

The FHWA is interested in structural steel detailing and fabrication innovations that may include, but are not limited to:

· Steel Bridge Stiffener Details to Avoid Constraint-induced Fractures (addressing issues with: typical design/fabrication experience, intersecting welds, web gap, plate thickness of bearing stiffeners and flanges, lateral force, out-of-plane distortion, etc.)

· Continuous Welding at Steel Girder Flange-web-stiffener Intersection (addressing issues with: corner clips of the transverse stiffener at the intersection, continuous weld at the intersection, residual stress and stress field, fatigue and fracture, effect to coating and painting, etc.)

Load Rating Program Topic: HIBS10-LR-001 Title: Risk-Based Methodology for Structural Evaluation of Bridge-Sized Culverts If a culvert meets the bridge definition in the National Bridge Inspection Standards and is subjected to highway live loading, it needs to be evaluated for its live load carrying capacity in accordance with American Association of State Highway and Transportation Officials (AASHTO) Manual for Bridge Evaluation (MBE). However, the AASHTO MBE only provides limited guidance for culvert evaluation criteria and methodology. Intuitively, not all culverts have the same risk from damage or failure resulting from highway live loads. The consequence of a culvert overload may be considered relatively benign as compared to a bridge overload, therefore the target reliability may also be less. However, this has not been established.

A risk-based approach would provide a methodology that allows for varying target reliability (and associated load and resistance factors) based on the likelihood and/or consequence of an overload. The risk depends on the geometric and material characteristics, physical condition of the culvert and its surrounding soil, as well as the load spectra and ADTT. Specifically, risk factors may include number of cells, overall dimensions, cell width and height, fill depth, condition rating, original design live load, maximum legal and permit loads, ADT, ADTT, detour length, repair or replacement cost etc. To gauge the risk, both probability of exceedance and its consequence need to be considered. It is expected that this research will investigate all relevant, critical risk factors and formulate a risk-based methodology for evaluating culverts. The research will also need to provide sufficient technical details and breadth appropriate to support the implementation for the key elements in the methodology. The FHWA seeks solutions for this topic which address the following:

1. Development of a risk-based framework for culvert structural evaluation

2. Determination of key factors affecting risk

3. Proposed target reliability and associated load and resistance factors for different risk levels

4. Data needs and sources for full LRFD calibration

5. Implementation strategy that allows for qualitative approach (now) and calibrated approach (future) Seismic and Multi-Hazzard Program Topic: HIBS10-SMH-001 Tittle: Framework and Methodology for Risk-Based Bridge and Tunnel Asset Management The performance of bridges and tunnels must support the mission of the highway network in providing uninterrupted operation for the daily transportation needs, as well as evacuation capacity and emergency service function before/during/after extreme events. States may achieve the best possible transportation network performance through a properly planned asset management strategy. Current engineering practices are relatively simplistic and subjective in this area. New methodology is needed that is more comprehensive and risk-based. It should provide consideration of all credible risks and the change of consequences when alternative actions are selected for bridges and tunnels. This new methodology needs to examine both regular operation, such as daily traffic fluctuation or planned maintenance/construction, and extreme events that have recurring intervals significantly greater than bridge design life span. The risk quantification from extreme events is very different than that for events that occur regularly (such as daily truck traffic) and events that we can decide whether/when/how (such as maintenance/construction work). The FHWA is interested in new frameworks and methodologies for risk-based asset management of bridges and tunnels that provide comprehensive consideration of extreme events, and address key items such as:

1. Proper metrics and procedures that connect structural performance to transportation performances with consideration of the effect of extreme events.

2. Case studies and scenarios showcasing applications and alternatives analysis.

3. Gaps in knowledge and data for all factors involved.

Topic: HIBS10-SMH-002 Tittle: Modeling and Analysis Tools for Risk-Based Bridge and Tunnel Asset Management The effects from various bridge and tunnel asset management approaches that consider risks from extreme events may include changes in direct cost, indirect cost, safety, and sustainability. To support proper alternative analysis and decision-making, costs from all stages of bridge life and loss for the community caused by extreme and non-extreme events must be quantified with a robust modeling and analysis tool. Ideally, engineering data (inventory, fragility), transportation function (OD, detour, commodity/passenger flow, tonnage-mile cost), safety data (casualty with respect to various scenarios) would all be considered. To accomplish this, we may choose to create an all-inclusive tool that unifies various risk measurements, or we may choose to continue individual development and summarize by a general analysis tool. A multi-objective optimization capability is potentially useful for summarizing various factors described above. The FHWA is interested in modeling and analysis tools and relevant data that can support optimal decision-making in managing bridges and tunnels with consideration of extreme events. The solution should address key items such as:

1. Development of tools for evaluating decision-making variables/indices.

2. Methods and suitable indices for considering consequences that are measured by different metrics.

3. Consistent approaches in multi-objective optimization that minimize any potential biases.

4. Existing data and potential needs of further development or processing of relevant data.

Bridge and Tunnel Security Program Topic: HIBS10-BTS-001 Tittle: Security and Safety of Bridges from Human-made Hazards Background: Resilience and security contribute to the overall safety of bridge systems which are potentially exposed to human-made (intentional) or extreme non-natural (accidental, and intentional such as a tanker truck fire) hazards. Efforts are needed to continue to advance the state of knowledge through research and development (R&D) and to implement the results through active deployment, technical guidance, specification language, and training. It is envisioned the R&D will focus on strategies to mitigate against collisions (including overhead impacts), developing blast mitigation designs for new and existing critical structures too important to fail, exploring the use of new materials for mitigation, bridge fire safety, and developing associated technical guidance. Research may also include developing test methods and acceptance criteria to assist owners in defining contracting language and technical requirements for major projects. While the focus on developing blast protection measures, it is expected to explore other load types or emerging intentional (such as an Improvised Explosive Devices or IED delivered by an Unmanned Aircraft System or UAS) hazards that can affect bridges and structures with detrimental consequences on transportation operations. The FHWA seeks solutions that address the following objectives and technology focus areas:

Objectives:

· Evaluate solutions to mitigate against human-made hazards that could potentially cause the collapse or reduce the resiliency and safety of bridges systems.

· Develop specifications for evaluating performance as acceptance criteria that could either include validated and verified analysis methods or experimental methods.

· Produce references or documents as part of best practices for dissemination to stakeholders.

Technology Focus Areas:

1. Bridge Security Engineering and Design

2. Physical Security Protection Measures that includes performance of new advanced materials

3. Collision mitigating solutions for guardrail improvements and overhead impact protection. Improvement and Barrier Development and Deployment

4. Fire Safety of bridge systems.

5. Emerging threat analysis and likelihood estimation methodologies.

6. Improvement to assessing and managing risk for terrorist threats to bridges and tunnels

Fiber-Reinforced Polymer (FRP) Composite Technology Topic: HIBS10-FRP-001 Tittle: Safety Inspection and Evaluation of Bridges with FRP Composites Fiber-Reinforced Polymer (FRP) Composite has been recognized as a class of material acceptable for both repairs of existing structures and new construction applications. For existing structures, bridge strengthening techniques using FRP composites are employed by bridge owners and bridge engineers to restore capacity or add capacity for a bridge to remain open to legal and unrestricted loads. FRP gives owners and engineers the ability to provide solutions to address emergency situations in a timely manner. For new construction, lightweight and corrosion resistance are the advantages of FRP composite bridge decks, Carbon Fiber Reinforced Polymer (CFRP) pre-stressing strands, Glass Fiber Reinforced Polymer (GFRP) rebars, and FRP pultruded structural members.

In 2018, AASHTO released the second edition of its “LRFD Bridge Design Guide Specification for GFRP-Reinforced Concrete.” This revised second edition includes consideration of flexural members, substructure and foundation elements, compression members, revised shear design methodology, and revised title to the first edition issued in 2009. Also in 2018, AASHTO released the first edition of its “Guide Specification for the design of Concrete Bridge Beams Prestressed with CFRP Systems.” This guide specification is the result of the completed National Cooperative Highway Research Program (NCHRP) 12-97 research. Another NCHRP effort is on-going, NCHRP 20-07/Task 428, to update the 2012 AASHTO Guide Specification for Design of Bonded FRP Systems for Repair.

Recent publications of these design guide specifications show that the design aspect of FRP Composite has matured over the years. However, other aspects of FRP Composite application in bridges are not yet fully addressed, which often discourage bridge owners and State DOTs from using the materials and technology. The FHWA seeks solutions to address the following items:

1. Inspection and Coding methods to conform with National Bridge Inspection Standard (NBIS)

2. Load Rating criteria and methods to conform with NBIS

3. Maintenance and repair methodologies of FRP reinforced and/or strengthened structures.