AASHTO Committee on Bridges and Structures T-9 Update

AASHTO MaC Bridge Technical Working Group – T-9 Update August 11, 2021 1

AASHTO Committee on Bridges and Structures T-9 UpdateGraham Bettis, P.E.TxDOT State Bridge Engineer

August 11, 2021


T-9 Bridge Preservation Membership

Jim Nelson, Iowa DOT (Chair)

Jeff Pouliotte, Florida DOT (Vice Chair)

Raj Ailaney, FHWA (Liaison)

David Miller, Louisiana DOT (Liaison)

Pe-Shen Yang, Arizona DOT

Anne Rearick, Indiana DOT

Ed Lutgen, Minnesota DOT

Kathy Crowell, New Mexico DOT

Ray Mabey, Oregon DOT

Graham Bettis, Texas DOT

Becky Nix, Utah DOT

Kendal Walus, Virginia DOT

William Pines, Maryland Transportation Authority


Strategic Plan for AASHTO Committee on Bridges and Structures

Goal 1: Extend Bridge Service Life

Goal 2: Assess Bridge Condition

Goal 3: Maintain and Enhance a Knowledgeable Workforce

Goal 4:Maintain and Enhance AASHTO Specifications

Goal 5: Accelerated Bridge Delivery and Construction

Goal 6: Optimize Structural Systems

Goal 7: Model and Manage Information Intelligently

Goal 8: Contribute to National Policy

Bonus AASHTO T-9 Goal: Identify and facilitate the advancement of state-of-the-practice through research.


AASHTO Guide to Preservation Actions

Goal 1: Extend Bridge Service Life

Just published!

Guidance on selecting specific, cost-effective preservation and maintenance actions.

Goal is to extend service life and estimate needed budgets to optimize performance.

Specifically:

– Bridge Preservation Actions

– Cost and Time Intervals

– Preservation-Cycle Cost Analysis

– Monetized Benefits of Preservation


Bridge Deck Preservation Tool

Goal 2: Assess Bridge Condition Part of Transportation Pooled Fund Program 5(474):

Bridge Deck Preservation Portal

– Indiana, Iowa, Minnesota, Missouri, Texas. Who else wants in???

Developing a Web-Based Bridge Deck Preservation Portal Tool

– Portal implies sharing of information.

– This is a tool, not a portal, with the intent that it will generate answers.

Developing data-driven approach.

Tool will provide various options depending on defects and life cycle goals.

Will develop User Manual and Webinar-based training and presentations to promote use of BDPT.


Bridge Deck Preservation Tool

Image Courtesy of James Nelson, Iowa DOT


Goal 3: Maintain and Enhance a Knowledgeable Workforce

AASHTO Guide to Preservation of Highway Bridge Decks: Educational webinar completed April 7, 2021.

Collaborating with the FHWA on Instructor Led Training for the Guide Specification for Service Life Design of Highway Bridges


Goal 4: Maintain and Enhance AASHTO Specifications

Six specifications or guides currently under T-9 purview.

– Guide to Preservation of Highway Bridge Decks, 1st Ed. –Passed COBS July 2021 – Future publication (likely mid-2022).

– Guide to Bridge Preservation Actions, 1st Ed. (BPA-1) –published July 2021.

– Historic Bridge Preservation Guide, 1st Ed. (HBP-1) –published November 2020.

– Guide Specification for Service Life Design of Highway Bridges, 1st Ed. (HBSLD-1) – published August 2020.

– Guide for Design and Construction of Near-Surface Mounted Titanium Alloy Bars for Strengthening Concrete Structures, 1st Ed. (NSMT-1) – published March 2020.

– Bridge Aesthetics Sourcebook, 1st Ed. (BAS-1) –published 2010.


Coating System Warranty Research

This one also discussed with MaCBridge TWG.

Ultimately not supported by AASHTO Committee on Bridges and Structures.

Florida DOT now pursuing via state-funded research.


AASHTO Guide to Preservation of Highway Bridge Decks

Part of NCHRP 14-36: Proposed AASHTO Guide for Bridge Preservation Actions

Effort led by Dr. George Hearn of University of Colorado at Boulder.

Lots of comments from State DOT’s and other stakeholders.

– Great deal of effort from Jim Nelson and Dr. Hearn to consider each comment and either take them into account or explain why recommendations were not incorporated.

– Emphasis that this will be a guide, not a specification.

Image Courtesy of Dr. George Hearn, University of Colorado Boulder


AASHTO Guide to Preservation of Highway Bridge Decks

Includes Cost/ Benefit for various actions that can be taken, similar to Life Cycle Cost Analysis.

Given different defects and desired goal, provides different options for maintenance or repair.

Deck Condition:

– Though it addresses decks in Poor condition, focus is on bridges still rated Good or Fair.

– Recognizes that it is frequently no longer practical to try and preserve a bridge deck that is in poor condition.


Addressing Locally Owned (Off-System) Bridges

Lots of discussion and interest right now on finding ways to expand bridge preservation efforts on bridges owned by local municipalities.

T-9, TSP2 (including a working group), Bridge Preservation Expert Task Group, FHWA


EDC-6: UHPC for Bridge Preservation and Repair

FHWA offering virtual and on-site webinars. Contact Dr. Zach Haber.

Not just about overlays and closure pours anymore; beam end repairs and other applications starting to catch on.

Images and Notes Courtesy of FHWA (Dr. Zach Haber)



Coming soon: FHWA-HRT-21 Report on UHPC Overlays

Lifecycle Cost Analysis Case Study

Comparison of UHPC with conventional solutions.

Break-Even analysis.

Focus on Delaware Memorial Bridge UHPC overlay project.




Developing UHPC design examples:

– Link Slabs

– Overlays

– Beam End Repairs

Easy to follow calculations.

Designs based on:

– Guide Specification

– Best Practices from State DOT’s

Also including drawings/ details.



NCHRP 20-05 (Topic 51-02) Study on Bridge Approaches

Synthesis Proposed by T-9: Design and Construction for Durability, Ride, and Water Management of Bridge Approach Systems.

Documents current state-of-practice for the design, construction, and maintenance of bridge approach slabs, pavement, and supporting elements.

Approach slab-to-abutment connections.

Geotechnical considerations for settlement and compaction of backfill.

Water management practices and drainage issues.

Image Courtesy of TxDOT and TTI



Literature review included design and construction methods for bridge approach system components, taken from State DOT’s.

Inspection of bridge approach systems based on Federal guidelines and several State DOT’s.

Investigated performance issues and mitigation strategies.

Image Courtesy of Dr. Mohamed ElBatanouny, WJE



National survey, with 44 DOT responses:

– Design and Construction of Bridge Approach Systems

– Water and Joint Management

– Operation and Maintenance

– Performance Issues and Mitigation Practices

Most Common Performance Issues:

– Bump formation at the joints on either side of the approach.

– Erosion.

– Failure of the sealant in the expansion joint.

Images and Notes Courtesy of Dr. Mohamed ElBatanouny, WJE


Best Practices in Bridge Detailing

COBS T-4 Construction Committee initiative, but lots of crossover with T-9.

Kathy Crowell with New Mexico DOT is project champion, with Dr. George Hearn of University of Colorado Boulder leading the effort.

Determining need and opportunity to develop an AASHTO Guide to Bridge Details.

Focus on:

– Approach Slabs

– Backfill (bump at the end of the bridge)

– Deck Panels

– Expansion Joints

– Deck Details (cover, thickness, drip grooves)

– Bridge Deck Overlays

– Slope and Bank Protection

– Integral and Semi-Integral Abutments

– Prefabricated Bridge Components


Best Practices in Bridge Detailing

Initial plan was to collect and catalog all State DOT bridge standards but quickly became apparent that would result in information overload.

Now seeking to collect what DOT’s deem to be their best standards that could be incorporated by other states.

Focus is on constructability and durability. Simple and repeatable is better than complex or unique for this one.

Trisha Bush (AASHTO) distributed survey from Cheryl Simmons (Utah DOT) on June 9th. Thus far heard from about half the states. Still looking for responses from:

Alaska Arizona Arkansas Connecticut Florida Hawaii Idaho

Indiana Kentucky Louisiana Maine Missouri Montana Nebraska

Nevada New Jersey North Carolina North Dakota Oklahoma Oregon Rhode Island

South Carolina South Dakota Utah Vermont Wyoming


T-9 UpdateQuestions or Discussion?Graham Bettis, P.E. – TxDOT State Bridge Engineer512-658-1231 (Mobile) [email protected]

August 11, 2021

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