Use of Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) for Fast and Sustainable Repair of Pavements
(UT Arlington IP No. 2019-45; UT Arlington patent under processing)
UHP-FRC Precast Pavement Implementation at Dallas/Fort Worth International Airport
This website provides a summary of the implementation of a U.S. Department of Transportation research project: “Use of Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) for Fast and Sustainable Repair of Pavements” sponsored through the Transportation Consortium of South-Central States (Tran-SET) under Project No. 17STUTA03 (see UTC newsletter).
- Principal Investigator: Shih-Ho Chao, Ph.D., P.E.
- Graduate research assistant: Ashish Karmacharya, MS.
The implementation was completely according to the technology developed in Project No. 17STUTA03 at the University of Texas at Arlington. The project report regarding the technical background can be found in: “Use of Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) for Fast and Sustainable Repair of Pavements.” (Readership Distribution around the world)
Summary of Project 17STUTA03:
This research presents a new methodology, which enables streets, roads, highways, bridges, and airfields to use an advanced fiber-reinforced concrete material, which can delay or prevent the deterioration of these transportation infrastructure when subjected to traffic and environmental loadings. The major problem of concrete is its considerable deterioration and limited service life due to its brittleness and limited durability. As a result, it requires frequent repair and eventual replacement, which consumes more natural resources. Ultra-high-performance fiber-reinforced concrete (UHP-FRC) introduces significant enhancement in the sustainability of concrete structures due to its dense microstructure and damage-tolerance characteristics. These characteristics can significantly reduce the amount of repair, rehabilitation, and maintenance work, thereby giving the transportation infrastructure a longer service life. This research addresses the strong need to develop fast and sustainable UHP-FRC materials for pavement repair that can be easily cast onsite without special treatments. This avoids any major changes to current concrete production practice and accelerates the use of UHP-FRC materials. This research investigated a new method for concrete repair by combining precast UHP-FRC panels with a small quantity of cast-in-place UHP-FRC for pavement repair without any dowel bars. In this method, a precast UHP-FRC panel is used along with cast-in-place UHP-FRC. The vertical repair surfaces of the existing concrete are roughened on site. The outer edges of the UHP-FRC precast panel are roughened before they are brought to the site (no dowel bars are needed). The depth of the precast UHP-FRC panel is the same as the existing pavement thickness. Only a small cast-in-place UHP-FRC joint (approximately four inches wide) is done onsite. The roughened precast UHP-FRC panel is placed in the repair area and cast-in-place UHP-FRC is cast into the joint. Experimental results showed that using a roughened surface (up to about CSP 5) provides a very large bond resistance, which is enough to prevent faulting.
Summary of Experimental Findings:
Presentation at Transportation Consortium of South Central States Conference:
Karmacharya, A. and Chao, S.-H. “Precast Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) for Fast and Sustainable Pavement Repair,” Transportation Consortium of South Central States Conference, San Antonio, TX, April 12, 2019.
Other Publications:
Karmacharya, A. and Chao, S.-H. “Precast Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) for Fast and Sustainable Pavement Repair,” Transportation Consortium of South Central States Conference, San Antonio, TX, April 12, 2019.
Karmacharya, A. and Chao, S.-H. “Use Ultra‐High‐Performance Fiber‐Reinforced Concrete (UHP‐FRC) for Fast and Sustainable Repair of Pavement,” Transportation Consortium of South Central States Conference, New Or leans, LA, April 3-4, 2018.
Karmacharya, A. Use of Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) For Fast and Sustainable Repair of Pavement and A New Sustainable Structural Member with Ultra-High-Performance Fiber-Reinforced Concrete (UHP-FRC) And Fiber-Reinforced Polymer (FRP) Reinforcement, M.S. Thesis, The University of Texas at Arlington, May 2019, 209 pages.
DFW International Airport Implementation:
- Task: Replacement of 24.5 ft x 18.5 ft x 17 in. (7.5 m x 5.6 m x 0.43 m) plain concrete pavement
- Design: three 18′-4″ x 7′-10″ x 17″ precast panels with 4″ joints all around (Designed by Dr. Shih-Ho Chao, UT Arlington)
- UHP-FRC mix design for this implementation: by Dr. Shih-Ho Chao (UT Arlington)
- Replacement task was completed within 6 hours, including demolition of old plin concrete pavement. UHP-FRC precast panels reached 5,000 psi in 16 hours.
Other participants of implementation at Dallas/Fort Worth International Airport (alphabetized by the last name):
Bhupendra Acharya (UT Arlington); Ahmed Alateeq (UT Arlington); Antonio Gallovich (Fiorigroup); Jean Gamarra (UT Arlington); Dr. Suyun Ham (UT Arlington); Pat McCollom (DFW International Airport); Binaya Pudasaini (UT Arlington); Mohammad Rehman (DFW International Airport); Dr. Rafat Sadat (DFW International Airport); Dr. Mohsen Shahandashti (UT Arlington); Dr. Thomas Taylor (Big R Bridge)
Photos:
Videos:
- UHP-FRC mix preparation:
- UHP-FRC Precast Pavement Panel Casting:
- UHP-FRC Precast Pavement Panel Surface Roughening:
- Placement of UHP-FRC Precast Panel after Demolition of Damaged Plain Concrete:
- Placement of UHP-FRC Precast Panel (last panel):
- Completing Cast-In-Place UHP-FRC Joint:
UHP-FRC Material Properties according to ASTM C1609 Testing
After Five Months’ Loading:
PRELIMINARY COST COMPARISON BETWEEN CONVENTIONAL AND UHP-FRC BASED AIRPORT PAVEMENT REPAIR METHODS (analysis carried out by Dr. Mohsen Shahandashti and Binaya Pudasaini, UT Arlington):
Assumptions:
- The length and the width of repair are taken as 22 feet and 18 feet, respectively. The depth of repair is taken as 10.2 inches (60% of 17 in. which was used for the implementation)
- The repair section is assumed to be a part of a critical runway in DFW airport.
- The entire runway has to be closed during the repair time due to safety considerations. Hence, the repair time is taken equal to the runway closure time.
- Labor costs and equipment costs are assumed equal for both the repair methods. Hence, it is not considered here for the comparison.
- Low life-cycle cost of UHP-FRC due to its high durability and toughness is not considered yet.
Cast-In-Place using Conventional Concrete and Construction
Material Costs: $125/yd3
Total repair Time before reopening the runway: 7 days
UHP-FRC Based Pavement Repair (Precast panel with minimal Casting-In-Place)
Material Cost for UHP-FRC pavement: $1500/yd3
Total repair Time before reopening the runway: 1 Day
Analysis based on:
- The Air Transport Association (ATA) estimated cost of closing runway
- 2019 RSMeans Heavy Construction Costs Book
- Historical Cost Index for January 2019 = 100.00
Runway Closure Cost for the DFW Airport for 2019 = $315,000
Conclusion
The cost of a typical airport runway repair using conventional approach is approximately six times that while using UHP-FRC based method.