This presentation discusses fiber reinforced concrete (FRC) pavements. It provides an overview of pavement problems like joints, different pavement designs including jointed reinforced concrete pavement (JRCP) and continuously reinforced concrete pavement (CRCP), and fiber options at different dosages. It summarizes research conducted by the Louisiana Transportation Research Center (LTRC) evaluating fatigue and toughness of FRC. The research found that macro synthetic fibers at dosages of 7.5-10.5 lbs/cu yd provided benefits over steel fibers. It concludes with summaries of several pavement projects using FRC with normal joint spacing.

1. FRC – Fiber Reinforced Concrete Pavements
Dan Biddle

2. This presentation is protected by U.S. and
International copyright laws. Reproduction,
distribution, display and use of the presentation
without written permission of the speaker is
prohibited.
©FORTA

3. FRC – Fiber Reinforced Concrete – Pavements

4. FRC Pavements
OVERVIEW
• Pavement problems
• Pavement design
• Fiber options
• LTRC research
• Projects – normal joints
• Projects – extended joints
• Fiber option review

5. U.S. highway system clearly needs help.
Pavement demands have grown while dollars have dwindled.
PAVEMENT PROBLEMS

6. A concrete pavement joint is
always a problem…a future
repair just waiting to happen.
PAVEMENT PROBLEMS
Michigan State Route 23 between Toledo
and Ann Arbor

7. “The Great Horse Manure Crisis of 1894.”
Pavement problems change with the times.
PAVEMENT PROBLEMS

8. Court Avenue, Bellefontaine, Ohio 1891
“Artificial stone” pavement…125 years and counting.
PAVEMENT PROBLEMS

9. Poor pavements are expensive for motorists:
• Faster vehicle wear & tear
• Reduced vehicle value
• Higher repair & maintenance costs
• Higher fuel consumption & tire wear
• Cost average driver $516 per year
PAVEMENT PROBLEMS

10. When considering driver costs – concrete is the material of choice.
Heavy vehicles cause greater deflection on flexible pavements than on rigid
pavements, causing up to 7% more fuel needed. And commercial truck
traffic will grow over 70% in the next 15 years.
PAVEMENT PROBLEMS

11. Joints are concrete pavement’s most vulnerable issue.
Reduction or elimination of pavement joints is an on-going goal.
PAVEMENT PROBLEMS

12. PAVEMENT PROBLEMS
Next target… exterior pavements.
FORTA® has a 15+ history of reducing joints in interior floor slabs.

13. • Long 30-60’ panels with mild steel reinforcement
• Load-transfer baskets at the joints
• Poor performance history – mid-panel faulting
• Essentially discontinued by 1990
PAVEMENT DESIGN
JRCP – Jointed Reinforced Concrete Pavement

14. JPCP – Jointed Plain
Concrete Pavement
PAVEMENT DESIGN
• Short unreinforced panels,
15 to 20’ long
• Load-transfer baskets at the
joints
• Currently most economical
pavement design

15. PAVEMENT DESIGN
• Continuous steel reinforcement
• No transverse joints
• Steel has no tensile or flexural
responsibility – only to hold cracks
tightly together: Let-it-crack
philosophy
• Cracks occur at spacing of 2-8 ft.,
generally less than 0.02 in.
• Best ride – most expensive
CRCP – Continuously Reinforced Concrete Pavement

16. Steel mat is labor-intensive and expensive in CRCP systems.
And steel corrodes.
PAVEMENT DESIGN

17. FRC pavement designs are dependent on dosage.
FIBER OPTIONS
1. Low dosage: 3-4 lbs. /cu. yd.
• Add-on to conventional jointed design
• Reduce cracking
• Improve toughness
Higher dosage = more opportunities

18. FIBER OPTIONS
2. Medium dosage: 4-7 lbs. /cu. yd.
• Reduce cracking – improve toughness
• Used in jointed designs
• Consideration of longer joint spacing is valid

19. FIBER OPTIONS
3. High dosage: 7.5+ lbs. /cu. yd.
• Reduce crack width opening
• Large improvement to toughness
• Dramatic increase to joint spacing
• Consider ‘joint-free’ pavement?

20. CFRCP – Continuously Fiber Reinforced Concrete
Pavement
FIBER OPTIONS
• Brainchild of Dr. John Kevern, Associate Professor of Civil
Engineering, University of Missouri at Kansas City
• Same concept as CRCP – enough reinforcement to allow
frequent tight cracks
• BUT…fibers must prove to hold cracks tight, i.e. < 0.02 in.,
under typical pavement conditions such as fatigue

21. A joint-free fiber-reinforced pavement would have many advantages…if
toughness and fatigue can be qualified.
FIBER OPTIONS
Comparison of CRCP, JPCP, and CFRCP
Pavement Type Benefits Shortcomings Difference in cost
CRCP • Smooth driving surface
• Fewer joint durability concerns
• Labor intensive
• Potential corrosion of steel
leading to durability issues
• Added steel cost
• More labor cost
JPCP • Less steel
• Less labor intensive than CRCP
• Joint maintenance • Lower steel cost than CRCP
• Less labor cost than CRCP
CFRCP • No steel
• Smooth driving surface
• Fiber cost comparable to steel
cost of CRCP
• Less labor cost

22. • June 2013
• Louisiana Transportation Research
Center, Baton Rouge, LA
• Research arm of LA-DOT
• Conducted in cooperation with U.S.
Department of Transportation,
Federal Highway Administration
• Casting at LTRC with LA-DOT materials
• Testing at UMKC concrete laboratories
LTRC RESEARCH

23. “Evaluation of the Fatigue and Toughness of Fiber Reinforced Concrete
for use as a New Highway Pavement Design”
LTRC RESEARCH
Dr. John Kevern, Associate Professor of Civil Engineering
University of Missouri – Kansas City
Dr. Tyson Rupnow, Associate Director of Research
Louisiana Department of Transportation

24. • 400 lbs. Portland cement
• 100 lbs. Class C fly ash
• 1,900 lbs. #67 limestone
• 1,266 lbs. natural concrete sand
• 250 lbs. water
• W/C = 0.50
• 5-7% air
LTRC RESEARCH
Concrete mix materials and proportions
standard LA-DOT pavement:

25. LTRC RESEARCH
Four fibers at multiple dosages tested:
1. Polypropylene fibrillated 1 ½” @ 1.5, 3.0 and 4.5 lbs. /cu. yd.
2. Polypropylene macro 2 ¼” @ 4.5, 7.5, 10.5 and 15.0 lbs. /cu. yd.
3. Carbon sheath 4” @ 9.0, 21.0 and 30.5 lbs. /cu. yd.
4. Type I hooked-end steel 2” @ 85 lbs. /cu. yd.

26. LTRC RESEARCH
Wide range of test parameters:
• Slump C-143
• Unit weight C-138
• Air content C-231
• 7-day compressive strength C-39
• 28-day compressive strength C-39
• Flexural strength C-78
• Toughness C-1609
• Fatigue at 90% and 70% stress levels
• Pre-cracked fatigue at 50% stress levels

27. LTRC RESEARCH
Fibrillated Polypropylene
• Toughness: showed little impact on post-crack behavior
• Fatigue @ 90% and 70%: > control < steel fibers
• Pre-cracked fatigue @ 50%: unable to hold pre-load, no values
• Too short and fine to contribute in a major way
Carbon Sheath
• Toughness: > steel fiber @ 21 lbs. for lower deflection
• Fatigue: > control, < steel fiber @ 90% ratio
> control, > steel fiber @ 9.0 lbs. @ 70% ratio
• Pre-cracked fatigue @ 50%: > steel fibers @ 21.0 and 30.5 lbs.

28. LTRC RESEARCH
Macro Synthetic Toughness
• At the 0.03” crack opening, macro synthetic @ 10.5 lbs. outperformed steel fibers
• The two highest ARS levels for macro synthetic fibers were 15.0 and 10.5 lbs./cu. yd.

29. LTRC RESEARCH
Toughness ARS @ 0.03” deflection
Polypropylene macro fibers
performed extremely well
compared to much higher
dosages of steel and carbon
fibers.
Carbon, 21.0 lbs.
Macro syn., 10.5 lbs.
Steel, 85 lbs.
Macro syn., 15.0 lbs.
Macro syn., 7.5 lbs.
Macro syn., 4.5 lbs.
Carbon, 9.0 lbs.
Fibrillated, 4.5 lbs.
Carbon, 30.5 lbs.
Fibrillated, 1.5 lbs.
Fibrillated, 3.0 lbs.

30. LTRC RESEARCH
Fatigue Testing
• Notched-beam method per University of Illinois protocol
• Beams tested at 90% and 70% ultimate flexural strength

31. LTRC RESEARCH
Pre-cracked Fatigue Testing
• Fibers were overwhelming the ability to crack – some beams exceeded 10 million cycles
• Pre-cracked the notched beams per ASTM C-1399
• Performed until failure (< 100 lbs.) or 1 million cycles

32. LTRC RESEARCH
Macro Synthetic Fatigue @ 90% Stress Ratio:
• All dosages > control
• 15.0 lb. dosage > 85 lb. steel fiber

33. LTRC RESEARCH
Macro Synthetic Fatigue @ 70% Stress Ratio:
• Began to show a more ductile mode of failure
• All four dosages > steel fibers
• Ex: Synthetic @ 4.5 lbs. = 6,400 cycles
Steel @ 85 lbs. = 500 cycles

34. LTRC RESEARCH
Macro Synthetic Pre-cracked Fatigue @ 50% Stress Ratio:
• Showed remarkable changes to failure mode: from
normal 4-stage failure to slower 2-stage failure
• When fibers at bottom began to fatigue and break,
fibers at top absorbed load and postponed failure
• Both 10.5 and 15.0 lb. dosages > 85 lbs. steel fibers

35. LTRC RESEARCH
Fracture face observations revealed:
• Macro synthetic = gradual fatigue and failure
• Steel = sudden and progressive failure
Holes Left by the
pullout of steel

36. LTRC RESEARCH
• Macro synthetic @ 7.5, 10.5, and 15.0 lbs. compared extremely well with carbon
and steel fibers
• When cost and user-friendliness are part of the equation, macro synthetic fibers
become very attractive

37. LTRC RESEARCH
LTRC Conclusions:
• At stress ratios of 60% and less, CFRCP outperforms JPCP; CFRCP will be
thinner than JPCP.
• Macro synthetic fibers increase the fatigue performance better than steel
fibers at the correct dosage.
• Macro synthetic fibers in the range of 7.5 to 10.5 lbs. / cu. yd. provides the
greatest combination of fatigue, toughness, and pre-cracked fatigue
performance.
• The use of fibers has an effect on the design thickness of pavements, resulting
in thinner pavements for low-stress, high-volume applications.

38. LTRC RESEARCH
LTRC – What’s next?
• Phase II : full-scale fatigue
loading of macro synthetic fiber
220 ft. panels, Baton Rouge
• Soliciting pooled-funding from
other DOT’s
• Searching for highway test
section to compare CFRCP to
JPCP and CRCP under same
conditions

39. PROJECTS: NORMAL JOINTS
J.M. Smucker – Orrville, OH 2009-2014
• Over 10,000 cu. yds. of FRC Pavements in a 5-year period
• FORTA-FERRO® 2 ¼” @ 4.0 lbs./cu. yd.
• 6” thick pavement with 15’ panels

40. PROJECTS: NORMAL JOINTS
Fed-Ex Freight – Conley, GA March 2011
• Converted from #3 bars @ 24” O.C.E.W
mat
• FORTA-FERRO® 2 ¼” macro fiber @ 3.0
lbs./cu. yd.
• 7 ½” thick pavement, 15’ x 15’ panels
• 4,400 cu. yds., 5 acres of trailer truck
pavement

41. PROJECTS: NORMAL JOINTS
Mineral Spring Street – Orrville, OH August 2012
• Converted from 4x4-W2.9xW2.9
WWF
• FORTA-FERRO® 2 ¼” macro fiber
@ 4.0 lbs./cu. yd.
• 9” thick pavement, 14.5’ panels,
2,700’ long

42. PROJECTS: NORMAL JOINTS
Old Dominion Freight – Phoenix, AZ December 2014
• Large freight-transfer hub, truck
pavement, parking, and dock slabs
• 18,000 cu. yds., conventional joint
spacing, no load-transfer baskets
• FORTA-FERRO® 2 ¼” macro fiber @
5.0 lbs./cu. yd.

43. PROJECTS: NORMAL JOINTS
Murphy Tractor – Zelienople, PA October 2015
• 330,000 sq. ft. of pavement and
parking for largest John Deere dealer
in W. Pennsylvania
• 7,000 cu. yds., 7” thick, 15’ x 15’
jointed panels, no load-transfer baskets
• FORTA-FERRO® 2 ¼” macro fiber @ 4.0
lbs./cu. yd.

44. PROJECTS: EXTENDED JOINTS
Atlanta Bonded Warehouse – Kennesaw, GA 2003
• Tractor trailer guard-house pavement
pad, over 150 trucks/day
• 40’ x 70’ x 6” joint-free panel on poor
substrate
• FORTA-FERRO® macro fiber @ 7.5
lbs./cu. yd.

45. PROJECTS: EXTENDED JOINTS
Aldi Paving – Springfield, OH October 2012
• 70,000 sq. ft. of car-park and pavement
• Jointed panels increased from 12’x12’ to 40’x40’, saving 7,000+ of sawcutting and joint filler
• FORTA-FERRO® macro fiber @ 7.5 lbs./cu. yd.

46. PROJECTS: EXTENDED JOINTS
McMaster Carr Paving – Douglasville, GA November 2014
• 300,000 sq. ft. of tractor trailer pavement for large distribution center
• Joints increased from 12’-15’ to 30’ or more, reducing joints and filler by > 50%
• FORTA-FERRO® macro fiber @ 7.5 lbs./cu. yd.

47. PROJECTS: EXTENDED JOINTS
Terrapin Trail – Orrville, OH September 2015
• City residential development street
• 29’ wide street, 9” thick
• Joints extended from 15’ to 30’, load
transfer baskets only at center-line joint
• FORTA-FERRO® macro fiber @ 5.0
lbs./cu. yd.

48. FIBER OPTION REVIEW
Current Pavement Design Issues:
• Joint deterioration is a major problem
• Steel corrosion is a major problem
• Pavement smoothness caused by curling is a major problem
• Durability and longevity are major problems

49. FIBER OPTION REVIEW
Macro Fiber Options:
1. Low dosage 3-4 lbs. = alternate to temperature steel,
reduced cracking, normal joint spacing
2. Medium dosage 5.0-7.5 lbs. = alternate to temperature
steel, added toughness, longer joint spacing
3. High dosage 9.0 lbs. = considerable fatigue
improvement, improvement to ride-ability, goal of
joint-free pavements

50. FIBER OPTION REVIEW
To achieve these performance goals, courtesy of these fiber dosages,
fibers must be user friendly!
• Uniform and easy mixing without balling
• Superior surface finish without whiskers
FORTA-FERRO® macro
synthetic twisted-bundle
gray fiber

51. FIBER OPTION REVIEW
Smooth, durable, cost-effective, reduced-joint pavements are available today.
FORTA-FERRO® provides the key to the pavement of the future.
• September 2011
• Residential driveway, W. Pennsylvania
• 155’ long x 10’ wide x 5” thick
• No joints – and no cracks

52. To learn more about FRC Pavements……
FORTA Corporation
100 Forta Drive
Grove City, PA 16127-6399 U.S.A
www.forta-ferro.com
1-800-245-0306