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FHWA continues to promote the use of UHPC for new construction, repair, and preservation. Updates related to UHPC will continue to be provided quarterly through this bulletin.
FHWA Publishes "Structural Design with UHPC”
FHWA recently published a pioneering report focusing on Structural Design with Ultra-High Performance Concrete (FHWA-HRT-23-077).
UHPC is a structural material that exhibits compelling structural behaviors. In comparison to conventional concrete, UHPC offers sustained postcracking tensile resistance, along with an increased compressive strength, an increased elastic modulus, and a decreased susceptibility to liquid permeation. To effectively engage the enhanced behaviors of UHPC, structural design guidance must rationally and conservatively provide a framework within which designers can appropriately conceive UHPC structures and proportion UHPC elements. With a look toward the future, UHPC can most likely allow for the design of novel structures whose composition is efficient, whose functionality is improved, and whose lifespan is extended.
The main body of the report provides an overview of UHPC in the context of structural design. The report also contains three appendices. The first, Appendix A—Guide Specification for Structural Design with Ultra-High Performance Concrete, contains a draft structural design framework developed for consideration by AASHTO and presented in the format commonly used for AASHTO guide specifications. Section 1 of Appendix A focuses on structural design guidance, while Section 2 focuses material conformance guidance. To assist readers in understanding the potential application of the proposed structural design framework, a pair of design examples has been developed to demonstrate some of the basic concepts embedded in the framework. The first example focuses on using the methods in the design framework to analyze the behavior of a rectangular beam. This example can be found in Appendix B—Analysis of a Rectangular, Mild Steel Reinforced UHPC Beam. The second example demonstrates the design of a slab-on-stringer bridge superstructure using pretensioned girders. This example can be found in Appendix C—Design Example of a Pretensioned UHPC I-Beam Bridge with a Conventional Concrete Deck.
The report can be downloaded for free at this link.
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FHWA Publishes "UHPC Link Slab Design Example"
FHWA recently published Ultra-High Performance Concrete (UHPC) Link Slab Design Example (FHWA-RC-23-0004). UHPC link slabs are one of the most promising applications of UHPC for preservation and repair activities. This report provides background, context, and foundational knowledge to bridge owners and designers interested in using UHPC link slabs for preserving our Nation's highway bridges.
This report explains the fundamental concepts behind and provides the design calculations for a UHPC link slab. In this design example, an existing four-span, steel simple-span composite bridge containing traditional expansion joints is used as the base structure. The example steps through the process of designing link slabs that will replace the three interior expansion joints on the bridge. Construction details for the existing structure and link slab design are provided. Calculations are provided to determine the longitudinal horizontal loads for the structure to evaluate the effect of the link slabs on the existing substructure and foundation elements. The redesign of the bearings is also included.
The report can be downloaded for free at this link.
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UHPC for Bridge Deck Rehabilitation Featured in District of Columbia Local Broadcast News Story
UHPC overlays was featured in a story on the local District of Columbia NBC station on Thursday, August 24, 2023. This technology, advanced by HRDI researchers, is supported through an EDC-6 initiative, and beginning to be deployed by the Washington, DC DOT and other owners across the country. The news story featured clips from FHWA promotional videos and included a soundbite from our own Ben Graybeal.
Link to the story: New, tougher concrete expected to expand lifespan of DC bridge – NBC4 Washington (nbcwashington.com).
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Are you looking to deploy an innovation on a highway project and need funding to offset the costs?
Applications Open for AID Demonstration Grants
The Accelerated Innovation Deployment (AID) Demonstration provides incentive funds to eligible entities to accelerate the implementation and adoption of innovation in highway transportation. FHWA has awarded 127 AID Demonstration grants at more than $95.7 million dollars since its launch in 2014. These funds can be used in any phase of a highway transportation project between project planning and project delivery, including planning, finance, operation, structures, materials, pavements, environment, and construction. The 2023-2026 AID Demonstration Program will make available up to $10 million in grants in Fiscal Year (FY) 2023 and $12.5 million in FYs 2024 through 2026. The Call for Applications for the 2023 cycle is open through January 24, 2024, and you can apply for AID Demonstration Grants at grants.gov.
Did you know that each STIC has access to $100,000 each year to support the costs of standardizing innovative practices in a state transportation agency or other public sector STIC. Learn about innovations your peers have deployed at STIC Incentive Projects (FY 2014-2022) | Federal Highway Administration (dot.gov) and follow the instructions at STIC Incentive Program Guidance | Federal Highway Administration (dot.gov). If you have questions, contact the EDC Coordinator in the FHWA Division Office.
Recent Publications Related to UHPC
FHWA has recently released numerous publications related to UHPC. Here is a summary:
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UHPC Link Slab Design Example (FHWA-RC-23-0004) - link
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Structural Design with UHPC (FHWA-HRT-23-077) - link
- “Assessing Durability Properties of Ultra-High Performance Concrete-class Materials” (Materials and Structures, Volume 56, September 2023) - link
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Ultra-High Performance Concrete (UHPC) Overlays: An Example of Lifecycle Cost Analysis (FHWA-HRT-23-012) - link
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Design and Construction of UHPC-Based Bridge Preservation and Repair Solutions (FHWA-HRT-22-065) - link
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Assessing Chloride Ingress Through Construction Joints in UHPC Overlays (FHWA-HRT-22-078) - link
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Techniques to Inhibit Corrosion in Bridge Deck Reinforcement Prior to Overlay Installation (FHWA-HRT-22-087) - link
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Electrical Resistivity Testing to Rapidly Assess the Durability of UHPC-Class Materials (FHWA-HRT-21-095) - link
- “Mechanical Behavior and Design Properties of Ultra-High Performance Concrete” (ACI Materials Journal, Volume 119, January 2022) - link
- “Flexural Behavior and Design of Ultra-High Performance Concrete Beams” (ASCE Journal of Structural Engineering, Volume 148, January 2022) - link
- “Shear Behavior of Ultra-High Performance Concrete Pretensioned Bridge Girders” (ASCE Journal of Structural Engineering, Volume 148, January 2022) - link
- "Shear Design of Strain-Hardening, Fiber-Reinforced Concrete Beams" (ASCE Journal of Structural Engineering, Volume 149, February 2023) - link
- “Interface Shear of Ultra-High-Performance Concrete” (ACI Structural Journal, Volume 119, January 2022) - link
- "Monolithic and Non-Monolithic Interface Shear Performance of Ultra-High Performance Concrete" (Engineering Structures, Volume 281, April 2023) - link
- "Prestress Loss Model for Ultra-High Performance Concrete (UHPC)" (Engineering Structures, Volume 252, February 2022) - link
More details on FHWA's work in UHPC can be found at this link.
Unless otherwise noted, all images sourced from FHWA.
The U.S. Government does not endorse outside entities, products, or manufacturers. Names are included for informational purposes only and not intended to reflect a preference, approval, or endorsement of any one entity or product.
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