Agenda

1
Synthetic Fibers in Precast

• Agenda
• Whats new
• Engineering fiber performance
• Synthetic Fiber benefits
• Rework reduction
• Green strength
• Crack control
• Steel replacement
• Reduced cycle time
• Financial payoff
• Summary

2
Synthetic Fibers in Precast

• Whats New
• Steel price - greater need for a fiber
  alternate
• Flexural reinforcement design - much wider uses
• Macrofiber technology - new fiber capabilities
• SCC technology - wider range of workability
• Synthetic fiber - proven to reduce production
  cost

3
Synthetic Fibers in Precast Whats new graph
Engineering News Record 20-City average rebar
price

• Reinforcing steel price up sharply
• Increase by 70 in 2004, additional increases
  forecast
• Significant price reduction seems unlikely
• Precast producers will probably benefit!
• Contractors are seeking alternates to steel
  construction
• Architects engineers are changing designs to
  precast
• Producers can get steel out of their product
• Microfiber alternate to temperature/shrinkage
  steel
• Macrofiber alternate to flexural steel

4
Synthetic Fibers in Precast Whats new

• Why use fibers in precast?
• Steel replacement - lower production cost
  labor materials
• Faster cycle time - lower plant overhead per
  unit
• Green strength - faster cycle time, lower cost,
  higher production
• Crack control - reduce rework costs, reduced
  rejects
• Reduced spalls - reduced rework costs, faster
  cycle time
• Appearance - reduced plant rework, reduced
  field cost

5
Synthetic Fibers in Precast Whats new

• Microfiber
• Fine, fibrillated
• Temp/Shrinkage steel alternate
• Macrofiber
• Coarse, monofilament, deformed
• Flexural steel alternate

6
Synthetic Fibers in Precast Engineering advances

• Three levels of concrete reinforcement based on
  area of steel ratio (AS)
• Temperature/Shrinkage reinforcement AS 0.1
• Flexural reinforcement AS lt 0.4
• Structural reinforcement AS gt 0.4

7
Synthetic Fibers in Precast Engineering advances

• Reinforcement measured by area of steel ratio
  (As)
• Example 4 rebar cage _at_ 12 each way, 6 thick
  wall
• 4 rebar 0.20 sq. in.
• Section 6 x 12 72 sq inches
• Ratio.0.20/72 x 100 0.27
• Requirements for precast
• 0.1 ACI 318 Temperature/shrinkage minimum
  steel
• 0.4 Modulus of flexural rupture of concrete

8
Synthetic Fibers in Precast Engineering advances

• Fiber use by area of steel ratio (As)
• Temperature/Shrinkage As0.1 Fibers clearly
  accepted
• Flexural reinforcement Fibers have proven
  effective
• Structural reinforcement Asgt0.4 Steel required

9
Synthetic Fibers in Precast Engineering
advancesIllustration shows vacuum testing
apparatus

• Septic Tanks A flexural reinforcement test
• Alabama tests - Vacuum tests per ASTM C 1227
• (3) 1000 gal tanks- fiber reinforced Failed at
  9.5-10.5 Hg
• Control tanks reinforced WWF - Failed at
  4.2 Hg
• California tests - Vacuum tests per ASTM C 1227
• (3) 1000 gal tanks- fiber reinforced sustained
  10.0 Hg w/o failure
• 10 hg is greater than 700 lbs/SF
• Substantially exceeds typical earth loads
• Provides confidence in design calcs.

10
Synthetic Fibers in Precast Engineering advances

• Septic Tanks IAPMO Spec PS 1-2003
• Establishes the standard of quality for septic
  tanks
• Concrete reinforced plastic
• Includes design requirements for fiber
  reinforcement
• Accepted in many jurisdictions
• Design Calculations are provided
• As by wall thickness requirement
• As converted to ASTM C-1399 flexural moment of
  resistance
• (Standard Test Method for Determining Average
  Residual Strength in Fiber Reinforced Concrete)
• Procedure for establishing fiber ASTM C-1399
  values (ARS)

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Synthetic Fibers in Precast Engineering advances

• Septic Tanks IAPMO Spec PS 1-2003

12
Synthetic Fibers in Precast Engineering advances

• ASTM C 1399 Average Residual Strength
• Crack the beam with spring-steel plate under
• Remove the steel plate
• Measure deflection under load (w/o PL)
• Average residual strength formula
• Section (sq.in.)
• Span length
• Test 5 beams
• ARS is a measure of post-crack strength (the
  level of load sustained by fibers in a concrete
  beam after the beam is cracked)

13
Synthetic Fibers in Precast Engineering advances
ASTM C 1399 - 5 pcy
Average Residual Strength (ARS) 215 psi
14
Synthetic Fibers in Precast Engineering advances

• Area of steel ARS values for synthetic fibers

15
Synthetic Fibers in Precast

• Agenda
• Whats new
• Engineering fiber performance
• Synthetic Fiber benefits
• Rework reduction
• Green strength
• Crack control
• Steel replacement
• Reduced cycle time
• Dosage
• Financial payoff
• Summary

16
Synthetic Fibers in PrecastRework Reduction

• Rework Reduction
• Extra cost to repair out of spec product.
• The cost of not doing it right the first time.
• Often not well recorded, can exceed 5 of total
  costs
• The rule of 10
• It costs 10x as much to fix it in the yard as
  doing it right in the plant
• It costs 10x as much to fix it on the job as does
  in the yard

17
Synthetic Fibers in Precast Rework Reduction

• Green Strength
• Improved early age handling strength (Green
  Strength)
• Allows faster cycle times
• Provides assurance against stripping/handling
  damage

18
Synthetic Fibers in Precast Rework Reduction

• Cracked or spalled product
• Shrinkage cracks during initial cure
• Handling cracks when product is relatively green
• Stripping shear or impact damage

19
Synthetic Fibers in PrecastSteel reinforcement
alternate

• Steel Costs stated /yard

20
Synthetic Fibers in PrecastSteel reinforcement
alternate

• Area of steel determination
• Determined by producers engineer
• Measured at a vulnerable section

21
Synthetic Fibers in PrecastSteel reinforcement
alternate

• Dosage Determination
• Per IAPMO PS 1-2003
• Partial steel replacement above AS 0.4

22
Synthetic Fibers in PrecastSteel reinforcement
alternateIllustration shows vacuum testing
utility vault, 20 Hg (1400 PSF)

• Application to Underground 6-sided Products
• Septic tanks
• Utility vaults
• Catch basins
• Weirs
• Drop inlets
• Grease traps
• Burial vaults
• Underground round products
• Manhole risers
• Dry wells
• RCP

23
Synthetic Fibers in PrecastCycle time reduction

• Cycle time
• The time to set, cast, cure and strip 1 piece
• The basis of labor cost and plant burden.
• Use of fiber reduces cycle time
• Green strength can mean stripping 2 hours earlier
• Eliminate steel means no cage to reset
• Reduced rework means rework product does not
  clutter plant
• Reduced rework means less supervisory burden

24
Synthetic Fibers in PrecastDosage

• Exceed the minimum dose
• Alternate to Temp/Shrinkage steel
• Temp steel .10, come up to the full design
• Allows for manufacturing handling variation
• Alternate to flexural steel
• Allows for manufacturing handling variation
• Reject pile why take a chance?

25
Synthetic Fibers in Precast

• Agenda
• Whats new
• Engineering fiber performance
• Synthetic Fiber benefits
• Rework reduction
• Green strength
• Crack control
• Steel replacement
• Reduced cycle time
• Dosage
• Financial payoff
• Summary

26
Synthetic Fibers in PrecastFinancial Payoff
Payoff for fiber use Septic Tank Example
27
Synthetic Fibers in PrecastSummary

• Fiber reduces production cost
• Rework reduction
• Green strength
• Crack control
• Steel replacement
• Steel savings and fiber costs are similar
• Reduced labor costs
• Reduced cycle time
• Increased production
• Lower burden

28
Synthetic Fibers in PrecastSummary

• There is a lot thats new in synthetic fibers
• Steel price renewed need for a fiber alternate
• New engineering - flexural reinforcement design
• New fibers - macro fiber technology
• New admixtures - SCC workability
• Engineering
• IAPMO septic tank spec and vacuum testing shows
  the way
• Fibers are becoming accepted in underground
  products
• Pipe manholes must overcome ASTM requirement
• Producers are using fibers and gaining confidence
• Fiber manufacturers are responsive
• Operational problems are being overcome
• Financial results are encouraging

29
Synthetic Fibers in PrecastSummary

• Who is Bill Ray
• Principal at Precast Consulting
• Background
• Business owner PCI certified producer
• General manager Sales exceeding 15 million
• Project manager Projects exceeding 10 million
• Chief fin. Officer Sales exceeding 150 million
• Education
• MBA University of Chicago
• BS Florida state
• Contact info 770-979-3711. billray_at_precastconsul
  ting.com