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    <title>Research in Progress (RIP)</title>
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    <atom:link href="https://rip.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Research in Progress (RIP)</title>
      <url>https://rip.trb.org/Images/PageHeader-wTitle-RIP.jpg</url>
      <link>https://rip.trb.org/</link>
    </image>
    <item>
      <title>Abrasion Resistance Comparison Wearing Surfaces</title>
      <link>https://rip.trb.org/View/2780489</link>
      <description><![CDATA[This project will evaluate and compare the abrasion resistance of Ultra High Performance Concrete (UHPC), Polyester Polymer Concrete (PPC), and standard concrete mixtures used for bridge wearing surfaces. Laboratory testing will be conducted using ASTM C944 and other applicable methods to compare material performance and assess current testing procedures. The results will be used to develop recommendations for abrasion resistance requirements and testing procedures to support ITD specifications and ensure adequate durability of concrete materials.
]]></description>
      <pubDate>Mon, 21 Sep 2026 15:58:59 GMT</pubDate>
      <guid>https://rip.trb.org/View/2780489</guid>
    </item>
    <item>
      <title>Granular Carbon-Enhanced High Early Strength Concrete for Bridge Decks</title>
      <link>https://rip.trb.org/View/2780485</link>
      <description><![CDATA[This project, conducted in collaboration with the City of Nampa, will evaluate the use of granular carbon as a concrete additive to improve early strength gain in bridge deck concrete while maintaining durability and workability. The study will examine how different carbon dosages affect concrete strength, workability, durability, permeability, shrinkage, thermal properties, and overall performance. Laboratory testing will be used to identify mix designs that balance strength, durability, constructability, and cost effectiveness. The project will also evaluate the potential for granular carbon to improve heat retention and reduce snow and ice accumulation on bridge decks.]]></description>
      <pubDate>Mon, 21 Sep 2026 15:20:35 GMT</pubDate>
      <guid>https://rip.trb.org/View/2780485</guid>
    </item>
    <item>
      <title>Residual System-Level Performance of Prestressed Girder Bridges with Cast-in-Place Decks after OHTI Repairs: Phase 1</title>
      <link>https://rip.trb.org/View/2780483</link>
      <description><![CDATA[This project will evaluate the performance of prestressed girder bridges with cast in place decks after over height vehicle impacts and repairs. The study will examine girder damage, repair methods, load distribution, diaphragm performance, and preloading to better understand how these factors affect long term bridge performance. The project will include a literature review, analytical modeling, and experimental testing. The results will be used to develop practical guidance for bridge inspections, load ratings, repair decisions, and future bridge design.]]></description>
      <pubDate>Mon, 21 Sep 2026 15:14:15 GMT</pubDate>
      <guid>https://rip.trb.org/View/2780483</guid>
    </item>
    <item>
      <title>Increasing the Lifespan and Resiliency of Bridge Deck Concrete Containing
SCM Through Durability-Based Performance Evaluation and Structural-Level</title>
      <link>https://rip.trb.org/View/2696935</link>
      <description><![CDATA[The long-term durability of concrete bridge decks is critical to ensure safe and cost-effective transportation infrastructure. While Supplementary Cementitious Materials (SCMs) are widely used to enhance the durability performance of bridge deck concrete, their long-term deterioration under both live-load and environmental (exposure conditions)-load remains inadequately understood. The research will evaluate in-service SCM bridge decks using Non-Destructive Testing (NDT) methods to track deterioration trends and correlate them with traffic loading and environmental exposure. Concurrently, representative SCM bridge decks will be constructed at the BEAST facility, where accelerated testing will simulate 15 to 30 years of traffic-induced damage through rolling loads, freeze-thaw cycles, and salt brine exposure, and deterioration progression will be monitored through the NDT assessments along with establishing a correlation between average daily traffic and bridge deck deterioration. The laboratory-based durability evaluation, followed by refinement of the TTI Tool, will be conducted at TTI for rapid and reliable durability-based performance evaluation (e.g., optimum SCM dosage for alkali-silica reaction mitigation; autogenous and drying shrinkage strains, shrinkage-based cracking potential; time to rebar corrosion initiation and probability of failure; and freeze-thaw service life based on estimation of time to critical saturation) of the selected SCM deck mixtures. A new and innovative combined approach (i.e., the TTI-Tool-based material level durability evaluation combined with performance prediction due to live-load + environmental load) will be developed for predicting the deterioration curve over time under field conditions for SCM field bridge decks. This will improve the durability and extend service life for new deck construction and improve repair strategies based on the remaining life prediction for the existing concrete bridge decks.
Developing this kind of combined approach aligns with NCIT’s focus on improving infrastructure durability by enhancing data-driven decision-making for bridge deck design, maintenance, and rehabilitation, and contributes to asset management and fostering more resilient transportation infrastructure.]]></description>
      <pubDate>Thu, 10 Sep 2026 08:27:23 GMT</pubDate>
      <guid>https://rip.trb.org/View/2696935</guid>
    </item>
    <item>
      <title>Investigating the Structural Impact of Delamination in Precast Concrete Panel Decks</title>
      <link>https://rip.trb.org/View/2768424</link>
      <description><![CDATA[Precast concrete panel (PCP) deck systems are the primary method for bridge deck construction in Texas. While these systems are designed to act compositely with a cast-in-place (CIP) concrete topping, recent field inspections and Ground Penetrating Radar (GPR) evaluations have identified widespread delamination at the PCP-CIP concrete interface. This bond degradation challenges the fundamental design assumption of monolithic behavior, which may lead to issues such as compromised punching shear capacity, reduced rigidity, increased deflection, water penetration, and potentially shortened service life. But the Texas Department of Transportation (TxDOT) currently lacks the data-driven, quantitative criteria necessary to evaluate the structural and serviceability implications of such distress. This research project addresses this critical knowledge gap by investigating how varying extents of delamination influence the bridge deck's serviceability, load-carrying capacity, fatigue resistance, and overall durability.]]></description>
      <pubDate>Thu, 27 Aug 2026 11:21:14 GMT</pubDate>
      <guid>https://rip.trb.org/View/2768424</guid>
    </item>
    <item>
      <title>Investigating Feasibility of Using Sileto for Bridge Deck Overlay</title>
      <link>https://rip.trb.org/View/2745141</link>
      <description><![CDATA[Bridge decks across the United States continue to experience deterioration due to
reinforcement corrosion, environmental exposure, and increasing traffic
demands. Traditional overlay materials such as normal-strength concrete and
some polymer-based systems often exhibit limitations related to durability, bond
performance, curing time, or long-term crack resistance. Sileto, as a viable
material for bridge deck overlays, has demonstrated promising mechanical and
durability characteristics in preliminary studies conducted by Florida International University (FIU) and Construction Technologies Laboratories (CTL), with compressive strengths approaching 12,000
psi at 28 days and durability behavior comparable to ultrahigh performance concrete (UHPC). However, its feasibility and performance as a bridge deck overlay system has not yet been
validated through comprehensive structural testing. To this end, the research will
combine small-scale material-level tests and large-scale structural tests to
establish bond behavior, durability, abrasion resistance, long-term performance
under cyclic loading, and overall structural capacity. The scope includes (1) direct
bond testing on small specimens to evaluate surface preparation methods and
overlay thickness effects; (2) freeze-thaw durability and long-term bond
assessment; (3) abrasion resistance testing in accordance with ASTM C944; and (4)
large-scale testing of a steel-girder-supported concrete deck upgraded with a
Sileto overlay, including five million load cycles followed by ultimate load testing
and post-test forensic evaluation. The results will provide critical performance
data, recommended construction protocols, and preliminary guidance for
implementation of Sileto as a practical overlay system. Outcomes of this project
directly support the Innovative Bridge Technologies/Accelerated Bridge Construction University Transportation Center (IBT/ABC-UTC) mission by introducing fast-curing, durable, and
field-deployable material that can reduce construction time, minimize traffic
disruption, and significantly enhance the service life of aging bridge infrastructure.]]></description>
      <pubDate>Fri, 07 Aug 2026 08:30:56 GMT</pubDate>
      <guid>https://rip.trb.org/View/2745141</guid>
    </item>
    <item>
      <title>Synthesis and Verification of Link Slab Practices for Jointless Bridge Decks in Accelerated Bridge Construction (ABC)</title>
      <link>https://rip.trb.org/View/2744923</link>
      <description><![CDATA[Bridge deck expansion joints are among the most maintenance-intensive
components of highway bridges, often leading to premature deterioration,
increased repair costs, and reduced service life. Link slabs provide an effective
alternative by enabling jointless deck configurations, improving durability, and
reducing long-term maintenance demands. Despite their proven benefits,
inconsistencies in design methodologies particularly regarding the need for deck
debonding and the use of advanced materials such as Ultra-High-Performance
Concrete (UHPC) have limited their broader adoption in Accelerated Bridge
Construction (ABC) applications. Early studies recommended partial debonding
near girder ends, while more recent large-scale investigations, such as SHRP2
R19A, concluded that debonding may not be required. At the same time, UHPC-based link slabs have demonstrated excellent crack control and durability, yet
remain without standardized design guidance. This project aims to synthesize
existing research, field applications, state DOT practices, and emerging material
innovations to establish practical best practices for link slab design. To this end,
the current study will (1) compile and evaluate past research and
implementations, (2) compare conventional and UHPC-based link slab
approaches, (3) conduct analytical and limited experimental verification to resolve
conflicting recommendations, and (4) develop design provisions and example
details suitable for ABC applications. The proposed work will produce a
comprehensive synthesis report, validated guidance, and actionable
recommendations for DOTs and practitioners. By clarifying design assumptions,
addressing uncertainties in debonding requirements, and evaluating the role of
UHPC, this study will promote the consistent and reliable use of link slabs in
jointless bridge decks.]]></description>
      <pubDate>Fri, 07 Aug 2026 08:21:45 GMT</pubDate>
      <guid>https://rip.trb.org/View/2744923</guid>
    </item>
    <item>
      <title>Condition Assessment Technology for Bridge Decks with Waterproofing Membranes</title>
      <link>https://rip.trb.org/View/2717329</link>
      <description><![CDATA[The condition assessment of reinforced concrete (R/C) bridge decks with waterproofing membranes and asphalt overlays is a significant challenge that has limited the use of this corrosion-protection strategy. State departments of transportation (DOTs) with existing inventories of bridge decks with waterproofing are unable to make effective repair and rehabilitation decisions because there is no way to assess the condition of the deck concealed by the waterproofing system. Some highway agencies do not use waterproofing membranes or asphalt overlays for the same reason.

 Bare R/C decks can be assessed easily by traditional methods such as sounding or chain drag, but bridge decks with a waterproofing membrane and asphalt comprise several layers of different materials that preclude the use of these traditional methods. Defects can occur within the R/C decks (delamination) or between the layers (debonding), and chloride-contaminated moisture can be entrapped between the layers. The presence of these subsurface defects affects heat flow through the multi-layer medium, producing subtle variations in the asphalt surface temperature, which are too small to be detected using conventional infrared thermography. More advanced nondestructive methods have also not proven successful. 

For NCHRP 20-30/IDEA 262, the research team will develop a new nondestructive technology based on time-lapse thermography to assess the condition of R/C bridge decks with a waterproofing membrane and asphalt overlay. The proposed research will explore if subtle surface temperature variations can be reliably detected by using a time-lapse thermography approach, which collects thermal data over time to assess time-varying thermal behavior rather than simply measuring surface temperatures. This helps increase sensitivity, potentially enabling more effective imaging of debonding, delamination in the R/C deck, and areas of entrapped moisture. The proposed technology serves a high-priority need of state DOTs that own in-service decks with waterproofing. 

Working with DOT partners (New Hampshire and Nebraska DOTs), deck materials will be evaluated to obtain more detailed information on the thermal properties of membranes in relation to the proposed measurement method. Measurement algorithms will be developed using a modeling and simulation approach that is currently being used for subsurface damage detection. Following laboratory characterizations to assess the measurement procedures and to obtain needed measurement parameters, field validation of the developed procedure will be performed.


]]></description>
      <pubDate>Tue, 23 Jun 2026 13:40:38 GMT</pubDate>
      <guid>https://rip.trb.org/View/2717329</guid>
    </item>
    <item>
      <title>Cracks of Low-P Rapid Set Concrete in Deck Repairs: Analysis, Prevention, and Alternatives</title>
      <link>https://rip.trb.org/View/2714454</link>
      <description><![CDATA[The occurrence of full-depth transverse cracks in Low-P rapid-set concrete highlights the need to investigate the cracking mechanisms in repaired bridge decks, as well as to develop prevention strategies and alternative materials.

OBJECTIVE: The overall objective of this project is to analyze the correlations between cracks in Low-P rapid set concrete and factors including concrete mix design, construction practices, curing conditions, and the service environment/weather conditions of bridge decks. This analysis aims to deepen the understanding of cracking mechanisms and to develop strategies for preventing crack formation in this special concrete. The outcomes will guide the treatment of deck repair materials for Massachusetts Department of Transportation (MassDOT) projects, ultimately enhancing the durability and longevity of repaired bridge decks.]]></description>
      <pubDate>Tue, 16 Jun 2026 16:19:59 GMT</pubDate>
      <guid>https://rip.trb.org/View/2714454</guid>
    </item>
    <item>
      <title>Control of Cracking in Concrete Bridge Decks</title>
      <link>https://rip.trb.org/View/2712183</link>
      <description><![CDATA[According to AASHTO LRFD Bridge Design Specifications (LRFD BDS), there are two main methods of bridge deck design. The more analytical “Strip Method” tends to place a limit on rebar spacing. The limit is based on crack width limitations developed for building beams and adapted in the American Association of State Highway and Transportation Officials
(AASHTO) for flexural reinforcement in deck slabs several decades ago. The implied maximum crack width, according to the provisions of AASHTO, Article 5.6.7, for moderate exposure to corrosion is 0.017 in. Such limitation has been shown in practice to be prohibitive when high-strength rebars, whether corrosion resistant or not, are used. In the meantime, there does not appear to be adequate evidence that longitudinal cracks across the main transverse reinforcement are as dominant as transverse cracks across the secondary longitudinal bars. The second method is the “Empirical Design Method” in Chapter 9 of AASHTO LRFD BDS. This method gives prescriptive reinforcement based on full-scale testing performed in Ontario, Canada, in the 1970s. Interestingly, the Empirical Design Method results in lower rebar quantities than the more rigorous Strip Method. Further, the Empirical Design Method has no requirement for flexural crack control equations. Thus, it appears that the mechanics of load transfer in deck slabs need to be fundamentally examined.

The objectives of this research, limited to reinforced concrete bridge decks supported on structural steel or concrete girders, are: (1) To develop a comprehensive understanding of the causes of cracking in cast-in-place concrete bridge decks that are placed on girders. This may include full-depth precast concrete bridge decks. (2) To develop methods of controlling cracks by the identified causes. Such methods shall include concrete material properties, rebar types and properties, chemical admixtures, and curing methods. (3)        To review and modify the current AASHTO provisions relative to crack control. This would include the provisions of Article 5.6.7—Control of Cracking by Distribution of Reinforcement. Such revisions should be based on a rational interpretation of the available body of knowledge in addition to actual field demonstrations. (4) To examine the serviceability requirements for the Strip Method (Article 5.6.7) and the Empirical Design Method (Article 9.7.2).]]></description>
      <pubDate>Tue, 09 Jun 2026 16:01:44 GMT</pubDate>
      <guid>https://rip.trb.org/View/2712183</guid>
    </item>
    <item>
      <title>SPR-5130: Computational Tool for Estimating the Service-Life of Concrete Decks and Slabs</title>
      <link>https://rip.trb.org/View/2709431</link>
      <description><![CDATA[The objective of this implementation project is to deliver a calibrated and accessible computational tool that the Indiana Department of Transportation (INDOT) can use to estimate the service life of concrete bridge decks, one-way continuous solid slabs, and T-beam bridges, and to evaluate maintenance and rehabilitation scenarios. The model methodology, developed under Joint Transportation Research Program (JTRP) projects 4840 and 4526, captures the long-term effects of construction defects, environmental exposure, and common maintenance actions on deck performance, enabling prediction of the evolution of deck condition ratings under different deterioration and intervention scenarios. A user manual and user interface will be developed, and several illustrative case studies will be prepared.]]></description>
      <pubDate>Wed, 03 Jun 2026 13:33:47 GMT</pubDate>
      <guid>https://rip.trb.org/View/2709431</guid>
    </item>
    <item>
      <title>High-Strength, Corrosion-Resistant Reinforcement for Empirical Deck Design </title>
      <link>https://rip.trb.org/View/2689407</link>
      <description><![CDATA[The Nebraska Department of Transportation (NDOT) seeks to maximize the long-term durability and minimize the lifecycle maintenance costs of the bridge deck for an upcoming major river-crossing replacement, where future deck rehabilitation or replacement would be exceptionally costly, disruptive, and hazardous. Although NDOT has adopted guidance intended to improve deck durability, current practices still rely primarily on empirical deck design provisions developed decades ago using Grade 60 reinforcing steel. These provisions specify total reinforcing area but do not require explicit evaluation of crack control parameters, do not account for the use of higher-strength reinforcing (e.g., Grade 80 or Grade 100), and do not provide direction on how reduced steel area enabled by higher yield strength may affect crack formation, crack widths, or long-term durability. At the same time, while recent European research has proposed durability-focused design approaches that incorporate explicit crack-width considerations, there remains significant disagreement within the research and practitioner communities regarding the extent to which crack width directly correlates with reinforced concrete durability. As a result, it is not yet clear whether or how such approaches should be adopted by NDOT; however, a thorough review and synthesis of this work is essential to inform any future deck reinforcement guidelines. As NDOT considers transitioning to higher-grade reinforcement to reduce material quantities and construction complexity, it currently has no validated methodology to configure bar size, spacing, and reinforcement ratios to ensure adequate crack control, residual crack behavior, and ultimate strength performance. ]]></description>
      <pubDate>Tue, 02 Jun 2026 12:26:14 GMT</pubDate>
      <guid>https://rip.trb.org/View/2689407</guid>
    </item>
    <item>
      <title>Implementation of Ultra-High-Performance Concrete (UHPC) Bridge Deck Overlays in Nebraska</title>
      <link>https://rip.trb.org/View/2689406</link>
      <description><![CDATA[The Nebraska Department of Transportation (NDOT) Project SPR-FY24(034) confirmed the superior mechanical and durability performance of Nebraska’s non-proprietary ultra high performance concrete (UHPC) mixtures, field implementation remains a critical missing step. Bridge deck overlays require substantially larger material volumes and longer placement durations than typical UHPC applications, such as joint connections or patch repairs. These factors introduce challenges in production logistics, equipment capacity, and quality control that must be validated under real construction conditions. Currently, NDOT and local contractors lack documented field procedures and specifications tailored to Nebraska’s climate, materials, and construction practices. Key uncertainties remain regarding surface preparation methods (e.g., milling versus hydrodemolition), on-site batching and mixing of large quantity using truck mixers, placement sequencing, construction joints, finishing, curing, and early-age strength verification. Without full-scale field demonstration and training, these unknowns limit NDOT’s ability to specify UHPC overlays in new or rehabilitation bridge projects. ]]></description>
      <pubDate>Tue, 02 Jun 2026 12:25:59 GMT</pubDate>
      <guid>https://rip.trb.org/View/2689406</guid>
    </item>
    <item>
      <title>Development and Optimization of Biochar-Infused Self-Heating Concrete for Bridge Deck Deicing, Strength, and Service Life</title>
      <link>https://rip.trb.org/View/2696157</link>
      <description><![CDATA[Ongoing advances in the understanding of the chemistry and physics of infrastructure materials are making it possible to endow concrete with functional properties that include electrical conductivity, active thermal management, and charge storage. In this proposal, the research team will exploit these advances to engineer concrete bridge deck materials that can be heated in cold weather to eliminate or prevent ice formation. This functional behavior will be produced by infusing the material with moderate doses of biochar, a nanoporous and electrically conductive additive that will enable the material to conduct electricity and thereby raise the material’s temperature by Joule heating. The advent of electrically conductive concrete (ECC) will greatly reduce or eliminate the need for deicing salts in cold weather, the latter which interferes with traffic patterns when applied and shortens the service life of bridge decks by salt scaling mechanisms. In addition, the formulations will be optimized for ideal self-heating and maximum possible compressive strength.]]></description>
      <pubDate>Mon, 27 Apr 2026 19:56:12 GMT</pubDate>
      <guid>https://rip.trb.org/View/2696157</guid>
    </item>
    <item>
      <title>Ultra-high performance concrete composite decks for long-span coastal bridges (OSU)</title>
      <link>https://rip.trb.org/View/2663233</link>
      <description><![CDATA[Coastal and marine environments present some of the most aggressive conditions for bridges, due to exposure to salt spray, high humidity, chloride ingress, and cyclic wet-dry cycles. Many of the nation’s longest span bridges are in and around tightly constrained coastal regions and these bridges commonly employ orthotropic steel decks (OSD) to reduce dead weight and improve structural efficiency. Conventional orthotropic steel plate decks are vulnerable to fatigue cracks in welded joints, deck plate corrosion, and deterioration of overlays under harsh environmental loading. Many of these OSDs are failing well short of their intended design lives. To overcome these limitations, this project will develop and validate a novel UHPC-composite steel rib deck system as a replacement for conventional OSDs for long-span bridges. Ultra-high performance concrete (UHPC) offers high compressive strength, ductility, low permeability, and durability. We propose to make relatively thin UHPC slabs composite with strategically embedded structural steel ribs to produce a direct replacement for conventional OSDs but with reduced weight, equivalent or better stiffness and load carrying capacity while mitigating past persistent fatigue and corrosion issues. 

The research consists of four (4) phases. First, conceptual design and modeling: we will create analytical and finite element models of composite deck panels, varying parameters such as rib geometry, spacing, shear connectors, UHPC thickness, and interface behavior. Second, fabrication and laboratory testing of prototype panels that will be constructed and tested under repeated load cycles modelling wheel loads on the deck surface, environmental (freeze/thaw, chloride exposure), and static failure tests to measure structural performance characteristics including stiffness, crack patterns, fatigue life, and ultimate capacity. Third, interface and connection optimization where shear connections between the UHPC and steel ribs will be optimized to produce reliable composite action and minimal slip under repeated loading. Fourth, develop design guidelines using test data to produce simplified design rules and apply the system concept to a real long-span bridge as a case study.
]]></description>
      <pubDate>Sat, 31 Jan 2026 12:05:58 GMT</pubDate>
      <guid>https://rip.trb.org/View/2663233</guid>
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