Post on 11-Apr-2017
Measurement of Infiltration Rates and the Rejuvenation of Pervious
Concrete Pavements
Manoj Chopra, Ph.D., P.E.Professor of Civil EngineeringUniversity of Central Florida
chopra@ucf.edu
University of Central Florida
Outline
Introduction Installation of Pervious Concrete Pavement Embedded Ring Infiltrometer (ERIK) Infiltration Testing – Pre and Post Rejuvenation Sustainable Porosity (System and Component) Infiltration Results Rejuvenation Results Conclusions
University of Central Florida
Background
Increased impervious surfaces linked to decline in surface water quality Nutrients Heavy metals Hydrocarbons
Using pervious/permeable pavements in low traffic load areas can help with Groundwater recharge Pollutant reduction Land-use reduction Water harvesting
University of Central Florida
Overview US EPA Recognizes Pervious Concrete as a BMP for
Stormwater Runoff Are being Considered as a part of the State Unified Stormwater
Rule in Florida to provide Potential Credit Open structure of PC may get clogged due to entrapment of
sediment Initial Scope of UCF Research
Pervious Concrete Pavement Expanded Scope
Pervious Concrete Pavement (continued) Pervious Pavers – 2 Types Flexipave® - Recycled Rubber Tires Pervious Asphalt Recycled Glass Pavers Permeable Grout Paving Systems – 9 Types
4
University of Central Florida
Research Need
To collect data on long term hydraulic performance of pervious/permeable systems
To develop a reliable, non-destructive infiltration monitoring method
To determine effective porosity To determine in-situ infiltration data for clogged and
rejuvenated systems To determine strength data for several systems on the
market To determine impact on water quality
University of Central Florida
EVALUATION OF EXISTING PERVIOUS CONCRETE
INSTALLATIONS
Chopra, M, Kakuturu, S., Ballock, C, Spence, J and Wanielista, M. “Determination of the Infiltration Rates and the Effect of Rejuvenation Methods for Pervious Concrete Pavements, J. of Hydrologic Engineering, ASCE (Special Issue on LID), Volume 15, No. 6, pp. 426-433, 2010.
University of Central Florida
Initial Concept Embedded Single Ring Infiltrometer Double Ring Infiltrometer on the surface of
Pervious Pavement was found to Over-predict Rates due to Preferred Lateral Migration of Water
Led to Concept of Single Embedded Infiltrometer For Study of Existing Installations, Coring would
be required followed by installing a strong ring 12 inch Diameter (11-5/8” ID) with 11-Gauge
Steel Ring was Used
University of Central Florida
Embedded Single Ring Infiltrometer
11-5/8”
11-Gauge Steel
Subsoil
Pervious ConcreteCore
20”
6”
Advantages
1. One dimensional flow (no horizontal flow between pavement and soil)2. Representative of site existing conditions assuming same soil types, and concrete conditions.
Version 1.0 Late 2003
University of Central Florida
Field Site Reconnaissance Completed Field Sites
Vet Office in Sanford FCPA Office in Orlando Sunray StoreAway – Lake Mary Strang Communications – Lake Mary FDEP Office – Tallahassee
Other Regional Field Sites Greenville, South Carolina Atlanta, Georgia Savannah, Georgia Charlotte, North Carolina
University of Central Florida 10
Coring Operation at Existing PC Site
University of Central Florida 11
University of Central Florida 12
University of Central Florida
Field Test Results
Test Location
Avg. Concrete Rate [in/hr]
(Range)Avg. Soil
Rate [in/hr]Limiting Factor
Site 1 – Area 1 25.7 (19 – 32.4) 34.5 ConcreteSite 1 – Area 2 3.6 (2.8 – 4.5) 14.8 ConcreteSite 2 5.9 (5.3 – 6.6) 5.4 SoilSite 3 14.4 (2.1 – 22.5) 21.5 ConcreteSite 4 – Area 1 2.1 (0.7 – 4.5) 15.6 Concrete
Site 4 – Area 2 2.9 (0.9 – 4.9) 15.6 Concrete
Site 5 3.7 (1.7 – 5.4) 8.8 Concrete
*Age of concrete varies from 10 to 20 years (except for Site 4 – Area 1).
University of Central Florida
Control Tanks for Evaporation and Water Quality Testing
University of Central Florida
Establishing a Pervious Pavement Test Site at Stormwater Academy Pervious Pavements
Pervious Concrete Recycled Rubber Recycled Glass Porous Aggregates
Permeable Paver Pavements Removable Filler No Filler Permanent Permeable
Grout Joints
University of Central Florida
INSTALLATION OF PERVIOUS CONCRETE TEST SECTION
University of Central Florida
Forming
Florida Concrete Products AssociationOffice in Orlando
SWMA Test Facility
University of Central Florida
Placement and Screeding
Florida Concrete Products AssociationOffice in Orlando
University of Central Florida
Screeding and Rolling
University of Central Florida
Scoring and Curing
University of Central Florida
Finished Installation
Florida Concrete Products AssociationOffice in Orlando
SWMA Test Facility
University of Central Florida
University of Central Florida
IN SITU PERMEABILITY MEASURING DEVICE
Gogo-Abite, I, Chopra, M., Hardin, M., Wanielista, M. and Stuart, E., “In situ Permeability Determination Device for Porous Pavement Systems”, J. Irrigation and Drainage Engineering, ASCE, http://dx.doi.org/10.1061/(ASCE)IR.1943-4774.0000757. May 2014.
University of Central Florida
ERIK Device – Version 2.0
In-Situ, Nondestructive, Replicable
Constant Head Test Measures Pavement Infiltration
Rates Two types
System Recovery Type (4-inch embedment into parent soils)
Maintenance Indicator Type (2-inch embedment into sub-base layer)
University of Central Florida
Two Types of ERIK Device
Long-Ring ERIK How fast water enters
parent soils Evaluates system recovery Florida Water Management
Districts require a minimum of 2 in/hr
Short-Ring ERIK How fast water enters
pavement system Evaluates degree of surface
layer clogging
University of Central Florida
Typical Cross Sectional View of Embedded ERIK Device
(a)
(b)
152.4 mm pervious concrete
254 mm coarse sand (or Bold & Gold)
Filter fabric
Compacted subgrade(90–95% compaction effort)
20.7 MPa concrete curb(0–152 mm above pavement) 0% slope
Adjacent landscaping
Long-ERIK terminated 100 mm into subgrade
152.4 mm pervious concrete
254 mm coarse sand (or Bold & Gold)
Filter fabric
Compacted subgrade(90–95% compaction effort)
20.7 MPa concrete curb(0–152 mm above pavement) 0% slope
Adjacent landscaping
Short-ERIK terminated 25 mm into subbase
University of Central Florida
Typical View of Embedded ERIK Device
University of Central Florida
Plan View of Embedded ERIK Device
University of Central Florida
Views of Embedded Ring of the ERIK Device
Embedded ring
Ring-shaped gap for testing collar
University of Central Florida
Schematics of Measuring ERIK Device
University of Central Florida
Views of Measuring Unit of the ERIK Device
Graduated cylinder
Testing collar
Control valve
University of Central Florida
ERIK Device Test ResultsReproducibility and Repeatability
Both Short-ring and Long-ring ERIK devices
Coefficient of variation (COV) of test results
96% of COV were less than 7%
100% of COV were less than 10%
University of Central Florida
INFILTRATION RATES AND REJUVENATION TESTING
University of Central Florida
Testing Procedure
Measure infiltration rate of newly installed pavement
Clog pavement test section with 2 soil types Sandy soil Limestone fines
Measure infiltration rate of clogged pavement Rejuvenate pavement with vacuum truck Measure infiltration rate of rejuvenated
pavement
University of Central Florida
New Pavement Surface
University of Central Florida
Adding Sediment
University of Central Florida
Spreading of Sediment
University of Central Florida
Washing In of Sediment
Washed into the pavement pores
University of Central Florida
Infiltration Rate Testing of Clogged Pavement Surfaces
University of Central Florida
Rejuvenation (using Dry Vacuum)
University of Central Florida
Rejuvenation (using Wet Vacuum)
Vacuum sweeping of pavement surface
University of Central Florida
Rejuvenation (Pre-Saturation and Vacuum)
University of Central Florida
Pre and Post Rejuvenation - ERIK Testing
University of Central Florida
RESULTS: INFILTRATION RATES
University of Central Florida
Pervious Concrete Pavements: Long-Ring ERIK North Infiltrometer
University of Central Florida
Pervious Concrete Pavements: Long-Ring ERIK
South Infiltrometer
University of Central Florida
Pervious Pavements: Long-Ring ERIK
New Install Average In-filtration Rate [in/hr]
Clogged Average Infil-tration Rate [in/hr]
Rejuvenated Average Infiltration Rate [in/hr]
0
5
10
15
20
25
3026
13
17
Long-Ring ERIK Results for Pervious Pavements
Infil
trat
ion
Rat
e [in
/hr]
University of Central Florida
Pervious Concrete Pavements: Short-Ring ERIK
East Infiltrometer
University of Central Florida
Pervious Concrete Pavements: Short-Ring ERIK West Infiltrometer
University of Central Florida
Pervious Pavements: Short-Ring ERIK
100
1000
10000
1,432410 475
Short-Ring ERIK Results for Pervious Pavements
Infil
trat
ion
rate
[in/
hr]
University of Central Florida
Pervious Pavements: Long-Ring ERIK
0
5
10
15
20
25
30
PerviousConcrete
RecycledRubber
Pavement
Recycled GlassPavement
Perm
eabi
lity
[in/h
r]
Long-Ring ERIK Results for Pervious Pavements
New Average InfiltrationRate [in/hr]
Clogged AverageInfiltration Rate [in/hr]
Rejuvenated AverageInfiltration Rate [in/hr]
University of Central Florida
Pervious Pavements: Short-Ring ERIK
1
10
100
1000
10000
PerviousConcrete
RecycledRubber
Pavement
RecycledGlass
Pavement
Perm
eabi
lity
[in/h
r]
Short-Ring ERIK Results for Pervious Pavements
New Average InfiltrationRate [in/hr]
Clogged AverageInfiltration Rate [in/hr]
Rejuvenated AverageInfiltration Rate [in/hr]
University of Central Florida
SUSTAINABLE VOID SPACE(POROSITY)
University of Central Florida
Laboratory Testing for Porosity
University of Central Florida
Barrel Testing for Porosity
University of Central Florida
ResultsEFFECTIVE POROSITY
S/NO. MATERIAL Pre-Loading Post-Loading1 Pervious concrete 27.2 23.4
2 Flexi-pave 31.1 10.4
3 Permeable Pavers PP 9.1 19.6
4 Pea rock (#89) 36.5 12.5
5 HPF 39.0 15.0
6 Crushed concrete (#57) 41.4 1.4
7 Limestone (#4) 45.2 3.0
8 Granite (#4) 43.6 3.0
University of Central Florida
Recommended Effective Porosity Values
Type Sub-TypeSustainable Void
Space (%)Pervious Concrete 20Flexi-pave™ 20
Pervious PaversOld Castle 10Hanson 10
#4 RockLimestone 30Granite 30
#57 Recycled Crushed Concrete 25#89 Pea Rock 25
University of Central Florida
DESIGN AID SOFTWARE
Available for Download atwww.stormwater.ucf.edu
University of Central Florida
University of Central Florida
Slide #60
Example Problem #1For six (6) inches of pervious concrete * placed directly on top of the parent soil
Pull down menu for the type of pervious pavement
University of Central Florida
Slide #61
Example Problem #1For six (6) inches of pervious concrete * placed directly on top of the parent soil
If a storage reservoir is proposed, enter the
appropriate thickness of the material(s)
University of Central Florida
Slide #62
Example Problem #1For six (6) inches of pervious concrete * placed directly on top of the parent
soil, with a 7.5 inch rainfall depth:
System Storage (S’)
= 0.9”CN = 92Rational
“C” = 0.85
University of Central Florida
Slide #63
Example Problem #1Six (6) inches of pervious concrete * placed directly on top of the parent soil.
The FDOT Drainage Hydrology Handbook is available at:http://www.dot.state.fl.us/rddesign/dr/Manualsandhandbooks.htm
From the previous slide, the
Rational “C” = 0.85
For a 25 year design storm, the FDOT range for Rational
“C” values are:1.1 x 0.75 = 0.831.1 x 0.95 = 1.05 (use 1.0)
Similar results for sandy soils
University of Central Florida
CONCLUSIONS
University of Central Florida
Pervious Pavements (PC) – Infiltration Rates
Long-Ring ERIK – infiltration rate for the pervious pavement systems ≥ 2.0 in/hr.
Short-Ring ERIK All pervious pavement systems showed reduction
after clogging All pervious pavement systems showed increase after
rejuvenation to varying degrees Pervious Concrete showed a 67% reduction in
infiltration rate
University of Central Florida
PC Pavements – Infiltration Rate
Vacuum sweeping was shown to be an effective way to rejuvenate porous pavement systems
Pavement surface moisture condition had significant effect on the performance at vacuuming Dry soil – Vacuum worked well Damp soil – Vacuum not effective Saturated soil – Vacuum most effective
University of Central Florida
PC Pavements - PorosityPorosity plays an important role in designing porous pavement systems Total porosity not appropriate to use for design purposes Subbase aggregates will rarely have no moisture present As systems age, sediment will begin to accumulate and
decrease void space Sustainable porosity values are recommended for design
Average of effective porosity for clean sample and effective porosity for a sediment loaded sample
Closer to operating conditions while providing safety factor
Thank you!
Questions?