Mix Designs and using ASTM standards to ensure a high-quality final Pervious product. Walt Flood IV, M.S., P.E. IRMCA XXXtreme, 2018

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1 Mix Designs and using ASTM standards to ensure a high-quality final Pervious product Walt Flood IV, M.S., P.E. IRMCA XXXtreme, 2018

2 Who is Flood Testing Pervious Concrete Overview Pervious Concrete Mix Designs Pervious Concrete Testing -The ACI Guide way

3 Flood Testing Labs (FTL) was founded by Walter Flood in 1913 as one of the first testing labs in the Midwest. Located on the south side of Chicago Walter Flood III and Walter Flood IV are PE s in multiple states

4 General Material Testing Services and Consulting High Strength Concrete High Modulus Concrete Thermal Control Plans Maturity Monitoring NRMCA certifications Pervious and RCC Testing Special Performance Mixes Failures

5 What is Pervious Concrete? -ACI 522: hydraulic cement concrete proportioned with sufficient, distributed, interconnected macroscopic voids that allow water to flow through the material under the action of gravity alone

6 Why is Pervious Useful? Low Impact Development i.e. it can save us money Reduces stormwater volumes Naturally cleans and filters water Can be used for water collection/recycling Reduces urban heat island effect Safer surface (skid resistance) Eliminate Retention Ponds Provides a means to obtain LEED credits Makes a great fire pit

7 How is Pervious Pavement placed? -Placed in strips and compacted typically with roller screed -Immediately covered

8 What is Pervious Pavement? -Typical Sections ACI 522 ACI 522

9 Not this simple! -Zero fines -Zero slump -Standard concrete, take out the fines, remove some water and give it a try

10 Pervious Concrete Requires a producer to get in the lab a contractor to spend some money a mockup/ test placement jobsite adjustment with water 7 day cure covering with plastic consider the weather recurring maintenance Which is why so many screw it up!

11 More workable -More design work dialing in the gradation and laboratory properties -Smaller Topsize -6-8 slump

12 All starts from the aggregate Dry-Rodded Unit Weight (ASTM C 29) Used to determine free voids in aggregate - Provides baseline for mix designs - Get idea of range of voids

13 Empty Cubic Yard

14 Void space Solid Aggregate

15 Void space Paste Solid Aggregate Paste = Water, Cement, Sand (etc.)

16 Technically, don t need any more than water, cement; w/c typ Hydration stabilizer highly recommended Some #8-#16 sand increases freeze-thaw durability Fibers big help macro AE can t hurt Microsilica dense paste Viscosity Modifiers SAP, internal cure, MRWR Matt Offenberg

17 Divided into 3 major Groups: as re-organized in 522R (publish date TBD) Preconstruction/ mix development Construction testing Post Construction Evaluation

18 Testing Ideal: To measure the in-place properties of the material without damaging it, or create a specimen that can be tested that perfectly mimics the material as it is in place Method affects results Density example David Mitchell

19 Four ASTM standards relating directly to pervious testing C1688 Fresh Density and Void Content C1701 Field Infiltration Rate C1747 Raveling Potential C1754 Hardened Density David Mitchell

20 (also test panel placement) Aggregates -Dry-rodded Unit Weight (C 29) Confirmation/Choosing a Mix -Raveling Potential (C 1747) -Infiltration -Void-Density Curve (C 1688) -Tensile and Compressive Strength -Inverted Slump Cone -Gyratory workability -?

21 Void-Density Curve (ASTM C 1688) Used to create a Curve to control Quality -Identify target C 1688 Density ranges Very useful during placement

22 Move towards lab-only tests? Gyratory Compactor From Asphalt industry actually replicates rolling Use to determine mix properties -Correlate in Field with Density

23 Best Practices -Density and Unit Weight (C 1688) Experimental -Nuclear Density (is this really Post-Placement?)

24 ASTM C Density and Void Content of Freshly Mixed Pervious Concrete -Standard Air Meter Bucket -Compaction using Proctor hammer or Marshall Hammer -Two lifts 20 blows or two lifts 10 blows -For set mix, will provide measure of consistency

25 Fresh Density (ASTM C 1688) -Target from test panel Compare to Void-Density Curve -If outside the range, remedy truck -Frequency of testing? Walter H Flood III The PRIMARY means of control during placement

26 Nuclear Density Similar to ASTM D 2950 (asphalt), ASTM D 6938 (soils) Backscatter through plastic Provides moisture and density

27 To confirm compliance and monitor performance -Infiltration (C 1701) -Density and Void Content (C 1754) or Nuclear Density David Mitchell

28 ASTM C1701 Infiltration Rate of In Place Pervious Concrete -Nominal 12 Diameter Collar -Maintain.5 head of water (+/-.1 ) -Presoak with 8 lbs (1 gallon) -Test with 8 lbs or 40 lbs (1 or 5 gal) Recommending all Contractors perform CYA!

29 ASTM C1701 Infiltration Rate of In Place Pervious Concrete -Intended to indicate clogging Provides direct measure of water flow -Highly variable across single placement -Need lots of tests David Mitchell

30 ASTM C 1754 Density and Void Content of Hardened Pervious Concrete -Using 4 specimen -Trim to regular dimensions -Dry to constant mass -Method A 50C -Method B 95C

31 Hardened Density and Voids (ASTM C 1754) Provides standard method for Density and Voids -ACI requires 3 cores per 5000 sqft -Compare to results from TEST PANEL

32 Pervious Concrete maintenance -Issues at < 75 in/hr -Regain up to 95% infiltration with pressurewasher and vacuum

33 Scott Erickson

34 With proper work on the front end Quality Pervious is REAL!! Brian Lutey Thanks especially to: Brian Lutey, Ozinga Green Building Dave Mitchell, Bunyan Industries Jim Miller, C2 Products Dr. John Kevern, UMKC Scott Erickson, Evolution Paving Resources Flood Testing Laboratories, Inc.

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