Decks & Joints
Dimensional Stability of Grout-Like Materials Used in Field-Cast Connections
The wide use of grouts and grout-like materials in the construction industry is seen in applications such as joint sealing, structural repair, and connections in prefabricated bridge elements (PBEs). Currently, different types of grouts are available (e.g., epoxy-based, cementitious-based, etc.). The selection of the most appropriate grout type is commonly based on the application in which it is used and the desired performance. Grouts for transportation applications typically require high-performance properties such as rapid strength development and superior durability characteristics. However, dimensional stability issues (i.e., expansion and shrinkage) have been observed in various applications with different grout types but especially in cases where cementitious grouts were used, due mainly to their inherent shrinking behavior. This document provides information about the current approaches to quantifying the dimensional stability of grouts and grout-like materials, including those cementitious grouts known as “non-shrink cementitious grouts (NSCGs),” and highlights some of the limitations of the test methods currently in use. Additional material testing methods to better quantify dimensional stability are also proposed, as well as strategies to help mitigate some of the shrinkage observed in these types of materials.
Download the TechNote (.pdf)
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Bond of Field-Cast Grouts to Precast Concrete Elements
The performance of connections between prefabricated concrete elements constructed using field-cast cementitious grouts and grout-like materials is becoming a focus area for accelerated bridge construction (ABC) projects. These connections are required to provide sufficient strength and long-term performance equal to or better than the adjacent concrete elements that they are connecting to assure adequate stress transfer and long-term performance throughout the life of the bridge. Many aspects need to be taken into consideration when specifying the material to make these connections. The FHWA has issued a TechNote focusing on the aspects related to the bonding interface between the previously cast concrete element and the field-cast connection grouts, including test methods, factors affecting bond, and best practices for detailing and construction.
Download the TechNote (.pdf)
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Waterproofing Membranes for Concrete Bridge Decks
Concrete bridge deck deterioration is one of the most extensive bridge maintenance problems affecting the service life of bridges. One cause of the deterioration is the penetration of moisture and chlorides into the concrete with subsequent corrosion of the steel reinforcement. The use of waterproofing membranes is one strategy to prevent moisture and chlorides from reaching the concrete by providing a barrier on the top of the concrete deck. The waterproofing membrane is then protected from the traffic by an asphalt overlay.
The objective of this synthesis is to update NCHRP Synthesis of Highway Practice 220: Waterproofing Membranes for Concrete Bridge Decks on the same topic published in 1995. This synthesis documents information on materials, specification requirements, design details, application methods, system performance, and costs of waterproofing membranes used on new and existing bridge decks since 1995. The synthesis focuses on North American practices with some information provided about systems used in Europe and Asia.
Download NCHRP Synthesis 425
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Concrete Floor Moisture Testing – Relative Humidity Probes per ASTM F2170
The following short video, prepared by KTA-Tator, Inc., describes the process for determining relative humidity in concrete according to the ASTM F2170 test method.
View the Video
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Improved Testing Methods for Bridge Decks and Tunnel Linings
New nondestructive testing technologies are available to help transportation agencies inspect concrete bridge decks or tunnel linings more quickly and comprehensively. Information about Nondestructive Testing for Concrete Bridge Decks and Tunnel Linings (R06 A/G) is now available on the SHRP2 website
The Nondestructive Testing for Concrete Bridge Decks and Tunnel Linings web page features everything from PowerPoint presentations and research reports to a tool selection matrix and fact sheets. The website also provides information about the Implementation Assistance Program, as well as links to helpful resources, such as the Nondestructive Evaluation Web Manual and the NDT Toolbox, a web-based evaluation tool used to select appropriate NDT technologies for specific applications.
Nondestructive Testing for Concrete Bridge Decks and Tunnel Linings was developed through the second Strategic Highway Research Program (SHRP2). The suite of tools includes a number of geophysical, mobile-scanning, and hand-held technologies that help to define the actual extent of deterioration—beyond what can be seen—for improved repairs and real-time solutions. As a result, these tools can save transportation agencies time and money. The Pennsylvania Department of Transportation will host a product showcase on Nondestructive Testing for Tunnel Linings (R06G) on Sept. 14, 2016 in Pittsburgh, Pa. Those interested in attending should contact Dennis Sack at email hidden; JavaScript is required.
For more information about R06 A/G, contact:
Matthew DeMarco, FHWA, email hidden; JavaScript is required
Patricia Bush, AASHTO, email hidden; JavaScript is required
Pam Hutton, AASHTO, email hidden; JavaScript is required
Carin Michel, FHWA, email hidden; JavaScript is required
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Accelerated Bridge Construction to Rehabilitate Aging Highway Structures
Structure Magazine, October 2015
By Ric Maggenti, P.E. and Kenneth Brown, P.E.
In 1967, the San Mateo / Hayward Bridge incorporated the United States’ first orthotropic steel bridge deck on a major bridge, winning the American Society of Civil Engineers’ (ASCE) Outstanding Civil Engineering Achievement Award (OCEA). The mile-long orthotropic steel deck is included within the six-lane wide, two-mile long steel high-rise portion of the seven-mile long bridge. The two mile high-rise, spanning a navigation channel, was designed per the American Institute of Steel Construction’s (AISC) 1963 Design Manual. The San Mateo / Hayward Bridge is the longest bridge in the San Francisco Bay Area and the 25th longest in the world.
The riding surface placed in 1967 was an epoxy-modified asphalt concrete (EAC), and was now in need of replacement. Replacement materials for the riding surface were narrowed down to the original EAC that had performed so well and a premixed polyester concrete developed by Caltrans that has been performing well on concrete decks since 1983.
One major concern for replacing the riding surface was taking the bridge out of service during installation. This is a critical bridge connecting the East Bay Area communities to San Francisco, which made construction techniques even more important. It was shown that polyester concrete could be more adaptable to placement within tight time constraints.
Construction was performed primarily during two continuous 55-hour shifts over two weekends in May of 2015. The successful bidder was a joint venture of two California-based prime contractors pooling their capital and labor resources so as to focus on completing the tasks of removing the EAC and replacing it with a premixed polyester concrete on six lane-miles of riding surface. Detailed contractor planning and coordination of the vast amount of skilled labor and equipment on the bridge at one time, and owner inspection of the work with material quality assurance testing to ensure manufacturer’s quality control were vital to success. In contrast, the original 1967 surface placement time was three weeks at eight hours per day.
Read the Full Article
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Concrete Bridge Deck Deterioration
The MWBPP Working Group “Deterioration Modeling” has identified the report “Deterioration Rates of Minnesota Concrete Bridge Decks” as a deliverable product of related information.
Read the Minnesota Bridge Deck Report (.pdf)
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MWBPP: Bridge Deck Overlay Product Matrix
This matrix presents bridge deck overlay products and typical application thicknesses for the partnership states of IN, IA, KS, KY, MI, MO, NE, ND, OH, and SD. The final spreadsheet may be downloaded as an (.xlsx) file at:
Download the Final Spreadsheet (.xlsx)
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WBPP: Bridge Deck Overlay Product Matrix
This matrix presents bridge deck overlay technical, cost and performance information for all wearing surface products currently used in the western United States. The final report may be downloaded as a (.docx) file at:
Download the Final Report (.docx)
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NEBPP: Small Movement Expansion Joints in the Northeast
Past Experience and State-of-the-Practice
The Northeast Bridge Preservation Partnership (NEBPP) contracted with the University of Delaware to carry out an investigation and report on the state-of-the-practice with small movement expansion joints in the 12 partnership agencies.
Download the University of Delaware 113-page Report (.pdf)
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WBPP: Deck Seals – Product Matrix
The Western Bridge Preservation Partnership (WBPP) has produced a matrix listing all deck seals (and their properties) used by highway agencies within the WBPP region. The information listed should be of use to practicing bridge maintenance crews, inspectors, and designers in the selection of bridge deck crack sealer products.
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Deck Overlays – Product Matrix
The Western Bridge Preservation Partnership (WBPP) has produced a matrix listing all deck overlay products currently used by one of the Western Bridge Preservation Partnership (WBPP) states. The information listed should be of use to practicing bridge maintenance crews, inspectors, and designers in the selection of bridge deck wearing surface products.
Download the Bridge Deck Overlay Product Matrix (.docx)
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Michigan’s Experience with Flood Coats
Epoxy flood coats have been used as a preventive maintenance treatment on bridge decks in Michigan since the early 1990s. The early flood coats were expensive, time consuming and left many questions regarding effectiveness and longevity. Since then, improvements in materials and application made through state employee ingenuity and industry innovation have driven the price of doing a two-coat thin epoxy overlay in Michigan down to $3.80/sq. ft. and a penetrating healer sealer down to $1.80/ sq. ft.
Download a report describing Michigan’s experience (.pdf)
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Evaluation of Bridge Deck Sealers
The Colorado DOT has completed a study of four sealers commonly used on highway bridge decks and evaluated their relative performance.
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Deck Seals – Product Matrix
The Western Bridge Preservation Partnership (WBPP) has produced a matrix listing all deck seals (and their properties) used by highway agencies within the WBPP region. The information listed should be of use to practicing bridge maintenance crews, inspectors, and designers in the selection of bridge deck crack sealer products.
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Michigan DOT’s Deck Preservation Matrices
The Michigan DOT has published two versions of its Deck Preservation Matrix – one for decks with black rebar and one for decks with epoxy-coated rebar.
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Repair of Construction-Related Deterioration in Precast Deck-Panel Bridges
Precast, partial-depth deck panels have been used throughout the United States as stay-in-place forms and to provide a portion of deck strength. In Florida, fiberboard material was routinely placed along the
edges of the panels to seal the overlay of concrete, rather than embed the panels in grout. This approach did not allow the concrete to flow fully underneath the panel ends and did not provide a reliable, rigid bearing. The seriousness of this seemingly minor change in practice was only fully recognized nearly two decades later, when seven punching shear failures occurred on major highways. The attached paper reviews eight repair methods employed by the Florida Department of Transportation to maintain 200 deck-panel structures until they could be replaced. The paper highlights the difficulties that were faced in devising repairs when the underlying cause of the damage was not understood fully. Full-depth bay replacement with cast-in-place concrete was the most effective approach but required extended lane closures. Full-depth precast panels could be installed during nighttime lane closures but cost more. The most important lesson learned was that flexible materials, such as asphalt, were best avoided to repair the bridge decks.
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Iowa DOT’s Bridge Deck Epoxy Resin Injection Process
Iowa DOT has been using epoxy resin injections to prevent overlay delamination and extend bridge deck service life. The agency has now undertaken a research project to document the effectiveness of the process and has issued an Interim Report and a Tech Transfer Document.
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SHRP 2 Non-Destructive Toolbox Now Available
TRB’s second Strategic Highway Research Program (SHRP 2) has launched the NDToolbox—a web-based electronic repository of nondestructive testing (NDT) techniques. Information in the repository includes summaries of NDT technologies; documentation for recommended test procedures, protocols, and available standards and guidelines; samples of data output and guidance on interpreting and presenting results; and equipment features (including cost, availability, and specifications).
The NDToolbox includes NDT techniques that address the following:
- Evaluating concrete bridge decks;
- Using field spectroscopy devices to fingerprint commonly used construction materials;
- Gathering uniformity measurements on new hot-mix asphalt (HMA) layers;
- Identifying delaminations between HMA layers;
- Conducting real-time smoothness measurements on portland cement concrete;
- Continuous deflection pavement measuring; and
- Mapping voids, debonding, delaminations, moisture, and other defects behind or within tunnel linings.
To learn more about the NDToolbox, read SHRP 2 Report S2-R06A-RR-1: Nondestructive Testing to Identify Concrete Bridge Deck Deterioration. |
Bridge Deck Treatments – NCHRP 20-07 / Task 234
Guidelines for selecting bridge deck treatments for different deck conditions and deck materials are now available following completion of NCHRP Project 20-07 / Task 234. In addition, Mr. Paul Krauss of Wiss, Janney Elstner Associates, the study’s contractor, made a presentation on the topic at the 2011 National Bridge Preservation Conference at St. Louis, Missouri.
Download the Guidelines (.pdf)
Download the Krauss Presentation (.pptx)
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Concrete Technical Resources
The Michigan DOT has developed a Guide titled “Thin Epoxy Overlay / Healer Sealer Treatments on Bridge Decks”, and a publication titled “Alleviating the Effects of Pavement Growth on Structures”.
Download the Guide (.pdf)
Download the Publication (.pdf)
The American Concrete Institute (ACI) has developed a set of Repair Application Procedures.
The following procedures are included:
- RAP1 — Structural Crack Repair by Epoxy Injection
- RAP2 — Crack Repair by Gravity Feed with Resin
- RAP3 — Spall Repair by Low-Pressure Spraying
- RAP4 — Surface Repair Using Form-and-Pour Techniques
- RAP5 — Surface Repair Using Form-and-Pump Techniques
- RAP6 — Vertical and Overhead Spall Repair by Hand Application
- RAP7 — Spall Repair of Horizontal Concrete Surfaces
- RAP8 — Installation of Embedded Galvanic Anodes
- RAP9 — Spall Repair by the Pre-placed Aggregate Method
- RAP10 — Leveling and Re-profiling of Vertical and Overhead Surfaces
- RAP11 — Slab jacking
- RAP12 — Concrete Repair by Shotcrete Application
- RAP13 — Methacrylate Flood Coat
- RAP14 — Concrete Removal Using Hydrodemolition
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Waterproofing Membranes for Concrete Bridge Decks
This synthesis, which updates NCHRP Synthesis 220 on the same topic published in 1995, documents information on materials, specification requirements, design details, application methods, system performance, and costs of waterproofing membranes used on new and existing bridge decks since 1995. The synthesis focuses on North American practices with some information provided about systems used in Europe and Asia.
Nebraska Department of Roads (NDOR) Survey of Sealers for Bridge Decks and Superstructures
The NDOR recently distributed a survey to state and provincial DOTs seeking information on their use of sealers for bridge decks and superstructures. The survey results are summarized in the Survey Summary Matrix with the following attachments:
Illinois Deck Sealing Program
Illinois DOT is in the second year of a deck sealing program funded at $7M/year (state funds). The Department intends to re-seal every bare concrete deck on the state system once each 4 years. For 2011, the average total cost (using silane/siloxane sealers) was $0.46 / square foot. Read ILDOT Bridge Deck Sealing Guidelines.
