pervious concrete

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message Richard L. Hird P.E. CCS Senior Member Username: dick_hird Post Number: 26 Registered: 02-2004 Posted on Thursday, May 19, 2005 - 06:09 pm:    Last summer I attended a demonstration on the placement of pervious concrete. I understand that it is used in the southeast in storm water containment and LEEDS applications. I am looking for help in specifying this product for an application in Ohio. Any help would be appreciated. Anonymous   Posted on Thursday, May 19, 2005 - 06:18 pm:    PART 1 - GENERAL 1.1 SUMMARY A. This Section includes pervious exterior cement concrete pavement for the following: 1. Driveways and roadways. 2. Parking lots. 3. Walkways. 1.2 SUBMITTALS A. Product Data: For each type of product indicated. B. Design Mixtures: For each concrete pavement mixture. 1.3 QUALITY ASSURANCE A. Manufacturer Qualifications: Manufacturer of ready-mixed concrete products who complies with ASTM C 94/C 94M requirements for production facilities and equipment. B. ACI Publications: Comply with ACI 301, "Specification for Structural Concrete," unless modified by requirements in the Contract Documents. C. Mockups: Cast mockups of full-size section of concrete pavement to demonstrate typical joints, surface finish, texture, color, and standard of workmanship. 1. Coordinate core tests on mockup for weight, void percentage, and thickness as indicated. Test failure automatically requires removal of failed mockup, construction of new mockup and retesting at Contractor's expense. 2. Obtain Architect's approval of mockups before starting construction. D. Preinstallation Conference: Conduct conference at Project site to comply with requirements in Division 1 Section "Project Management and Coordination." 1. Before submitting design mixtures, review concrete pavement mixture design and examine procedures for ensuring quality of concrete materials and concrete pavement construction practices. Require representatives, including the following, of each entity directly concerned with concrete pavement, to attend conference: a. Contractor's superintendent. b. Ready-mix concrete producer. c. Concrete pavement subcontractor. PART 2 - PRODUCTS 2.1 FORMS A. Form Materials: Plywood, metal, metal-framed plywood, or other approved panel-type materials to provide full-depth, continuous, straight, smooth exposed surfaces. 1. Use flexible or curved forms for curves with a radius 100 feet or less. B. Form-Release Agent: Commercially formulated form-release agent that will not bond with, stain, or adversely affect concrete surfaces and will not impair subsequent treatments of concrete surfaces. 2.2 CONCRETE MATERIALS A. Cementitious Material: Use the following cementitious materials, of the same type, brand, and source throughout the Project: 1. Portland Cement: ASTM C 150, Type I or II, gray. 2. Blended Hydraulic Cement: ASTM C 595, Type IS, portland blast-furnace slag or Type IP, portland-pozzolan cement. B. Normal-Weight Aggregates: ASTM C 33, Class 4S coarse aggregate, uniformly graded. Provide one of the following aggregates from a single source: 1. No 8 coarse aggregate (3/8 to No. 16). 2. No. 89 coarse aggregate (3/8 to No. 50). C. Water: ASTM C 94/C 94M. D. Chemical Admixtures: Provide admixtures certified by manufacturer to be compatible with other admixtures and to contain not more than 0.1 percent water-soluble chloride ions by mass of cementitious material. 1. Retarding Admixture: ASTM C 494/C 494M, Type B. 2. Water-Reducing and Retarding Admixture: ASTM C 494/C 494M, Type D. 2.3 STONE RECHARGE BED MATERIALS A. Aggregate: 3/8 inch to 3/4 inch uniformly graded coarse crushed aggregate that meets AASHTO size number 57 grading per Table 4, AASHTO Specifications, Part I, 13th Ed., 1982 (p. 47) or as follows: Sieve Size Percent Passing 1/2" 100 1/4" 50-90 No. 10 0-10 No. 40 0-5 No. 200 0-0.8 2.4 CURING MATERIALS A. Moisture-Retaining Cover: ASTM C 171, polyethylene film or white burlap-polyethylene sheet. B. Water: Potable. 2.5 RELATED MATERIALS A. Fibrous Reinforcing: 1. Reinforcing Fibers: Virgin fibrillated polypropylene reinforcing fibers, designed and manufactured specifically for use in concrete; one of the following. a. Forta Corporation "FORTA CR" b. Fibermesh, Inc. "Fibermesh Fibers" 2. Furnish fibers in 1-1/2 inch lengths. B. Geotextile Fabric: Mirafi "180N," or approved. C. Impervious Liner: Permalon "PLY-X 150," or approved. D. Drainage Pipe: ASTM 2241 PVC, Class 200. E. Expansion- and Isolation-Joint-Filler Strips: ASTM D 1751, asphalt-saturated cellulosic fiber. F. Pavement-Marking Paint: Latex, waterborne emulsion, lead and chromate free, ready mixed, complying with FS TT-P-1952, with drying time of less than [3] [45] minutes. 1. Color: As indicated. 2.6 CONCRETE MIXTURES A. Prepare design mixtures, proportioned according to ACI 301, with the following properties: 1. Compressive Strength (28 Days): 2500 psi. 2. Water-Cementitious Materials Ratio at Point of Placement: Not less than 0.27 nor more than 0.35. 3. Mix Proportion: Aggregate, cement, water, and admixture per cu. yd. equal to 27 cu.ft. when calculated as a function of the unit weight determined in accordance with ASTM C 29 rodding procedure. Fine aggregate, if used, not exceed 3 cu. ft. and shall be included in the total aggregate volume. 2.7 CONCRETE MIXING A. Ready-Mixed Concrete: Measure, batch, and mix concrete materials and concrete according to ASTM C 94. Furnish batch certificates for each batch discharged and used in the Work. B. Fibrous Reinforcing: 1. Add fibers at the rate recommended by the manufacturer for the application indicated, but not less than 1.5 lbs per cu. yard of concrete. 2. Mix in accordance with manufacturer's instructions. PART 3 - EXECUTION 3.1 EXAMINATION A. Examine exposed subgrades and subbase surfaces for compliance with requirements for dimensional, grading, and elevation tolerances. B. Proceed with concrete pavement operations only after nonconforming conditions have been corrected and subgrade is ready to receive pavement. 3.2 PREPARATION A. Do not compact or subject subgrade under bed areas to excessive construction equipment traffic prior to filter fabric and stone bed placement. B. Remove areas of subgrade where erosion has caused accumulation of fine materials and where surface has been subjected to ponding. C. Bring subgrade to the line, grade, and elevations indicated. Any areas damaged by erosion, ponding, or traffic compaction shall be filled and lightly regraded before stone placement. 3.3 EDGE FORMS AND SCREED CONSTRUCTION A. Set, brace, and secure edge forms, bulkheads, and intermediate screed guides for pavement to required lines, grades, and elevations. Install forms to allow continuous progress of work and so forms can remain in place at least 24 hours after concrete placement. B. Clean forms after each use and coat with form-release agent to ensure separation from concrete without damage. 3.4 STONE RECHARGE BED INSTALLATION A. Install geotextile fabric over non-compacted subgrade with 16 inch overlapping seams. Anchor fabric a minimum of 2 feet beyond the recharge bed boundaries if not placed within edge forms. B. Place recharge bed stone in 8 inch maximum lifts. Keep equipment movement over storage bed subgrades to a minimum during placement. C. Fold geotextile fabric up sides of placed recharge bed stone in areas not placed within edge forms and protect with temporary edging until permanent boundary material has been installed. 3.5 JOINTS A. General: Form construction, isolation, and contraction joints and tool edgings true to line with faces perpendicular to surface plane of concrete. Construct transverse joints at right angles to centerline, unless otherwise indicated. B. Construction Joints: Set construction joints at side and end terminations of pavement and at locations where pavement operations are stopped for more than one-half hour unless pavement terminates at isolation joints. C. Isolation Joints: Form isolation joints of preformed joint-filler strips abutting concrete curbs, catch basins, manholes, inlets, structures, walks, other fixed objects, and where indicated. D. Contraction Joints: Form weakened-plane contraction joints, sectioning concrete into areas as indicated. Where no joints are indicated, install at 15 feet intervals. Construct contraction joints for a depth equal to at least one-fourth of the concrete thickness. 3.6 CONCRETE PLACEMENT A. Comply with ACI 301 requirements for measuring, mixing, transporting, and placing concrete and the following: 1. Mix Time: Truck mixers shall be operated at the speed designated as mixing speed by the manufacturer for 75 to 100 revolutions of the drum. 2. Transportation: The Portland Cement aggregate mixture may be transported or mixed on site and shall be used within one (1) hour of the introduction of mix water, unless otherwise approved in writing. a. The one (1) hour requirement can be increased to 90 minutes when utilizing an approved hydration stabilizer, as long as the temperature of the concrete does not exceed 90 degrees Fahrenheit. b. Under no circumstance will retempering of concrete be allowed after any water adjustments have been made to concrete delivered to the jobsite. c. Trucks used to transport the porous concrete shall have no more than 3 consecutive loads of material without hauling conventional concrete or rinsing. 3. Water: Water may be added to obtain the required mix consistency in accordance with ACI 301. a. Water adjustments made at the jobsite must be approved by an authorized representative of the concrete supplier. b. A minimum of 20 revolutions at the manufacturer’s designated mixing speed shall be required following any addition of water to the mix. B. Moisten subbase to provide a uniform dampened condition at time concrete is placed. C. Deposit and spread concrete in a continuous operation between transverse joints. Do not push or drag concrete into place or use vibrators to move concrete into place. 1. Pavement placement widths restricted to a maximum of 15 feet. D. Immediately screed pavement surfaces with a straightedge and strike off. E. Remove the top 1/2 inch from edge forms, lightly mist concrete paving surface, and cover concrete with moisture retaining cover. F. Compact with mechanical equipment of either slipform or form riding with a following compactive unit that will provide a minimum of 10 psi vertical force. G. Tolerances: 3/8 inch in 10 feet from profile grade. H. Commence initial floating using bull floats or darbies to impart an open textured and uniform surface plane before excess moisture or bleed water appears on the surface. Do not further disturb concrete surfaces before beginning finishing operations or spreading surface treatments. 3.7 CONCRETE PROTECTION AND CURING A. General: Protect freshly placed concrete from premature drying and excessive cold or hot temperatures. B. Comply with ACI 306.1 for cold-weather protection. C. Begin curing after finishing concrete but not before free water has disappeared from concrete surface. D. Curing Methods: Cure concrete by moisture-retaining-cover curing. 3.8 PAVEMENT TOLERANCES A. Comply with tolerances of ACI 117 and as follows: 1. Elevation: 1/4 inch. 2. Thickness: Plus 3/8 inch, minus 1/4 inch. 3. Surface: Gap below 10-foot- long, unleveled straightedge not to exceed 1/4 inch. 4. Contraction Joint Depth: Plus 1/4 inch, no minus. 5. Joint Width: Plus 1/8 inch, no minus. 3.9 PAVEMENT MARKING A. Allow concrete pavement to cure for 28 days and be dry before starting pavement marking. B. Sweep and clean surface to eliminate loose material and dust. C. Apply paint with mechanical equipment to produce pavement markings of dimensions indicated with uniform, straight edges. Apply at manufacturer's recommended rates to provide a minimum wet film thickness of 15 mils. 3.10 FIELD QUALITY CONTROL A. Testing Agency: Owner will engage a qualified independent testing and inspecting agency to perform field tests and inspections and prepare test reports. Tests are in addition to mockup tests required in Part 1. 1. Testing Frequency: Obtain at least 3 core samples and an additional 3 core samples for each 1000 sq. ft. or fraction thereof of each concrete mix placed each day. 2. Thickness: ASTM C 42; Average of all production cores shall not be less than the specified thickness with no individual core being more than 1/4 inch less than the specified thickness. 3. Void Structure: ASTM C 138; 15% minimum; 21% maximum. 4. Unit Weight: ASTM C 642; plus or minus 5 pcf of the design unit weight. 5. Compression Test Specimens: ASTM C 31/C 31M; cast and laboratory cure one set of three standard cylinder specimens for each composite sample. 6. Compressive-Strength Tests: ASTM C 39/C 39M; test 1 specimen at 7 days and 2 specimens at 28 days. a. A compressive-strength test shall be the average compressive strength from 2 specimens obtained from same composite sample and tested at 28 days. B. Strength of each concrete mix will be satisfactory if average of any 3 consecutive compressive-strength tests equals or exceeds specified compressive strength and no compressive-strength test value falls below specified compressive strength by more than 500 psi. C. Test results shall be reported in writing to Architect, concrete manufacturer, and Contractor within 48 hours of testing. Reports of compressive-strength tests shall contain Project identification name and number, date of concrete placement, name of concrete testing and inspecting agency, location of concrete batch in Work, design compressive strength at 28 days, concrete mixture proportions and materials, compressive breaking strength, and type of break for both 7- and 28-day tests. D. Additional Tests: Testing and inspecting agency shall make additional tests of concrete when test results indicate that requirements have not been met. E. Remove and replace pervious concrete pavement where test results indicate that it does not comply with specified requirements. F. Additional testing and inspecting, at Contractor's expense, will be performed to determine compliance of replaced or additional work with specified requirements. 3.11 REPAIRS AND PROTECTION A. Remove and replace concrete pavement that is broken, damaged, or defective or that does not comply with requirements in this Section. B. Drill test cores, where directed by Architect, when necessary to determine magnitude of cracks or defective areas. Fill drilled core holes in satisfactory pavement areas with portland cement concrete bonded to pavement with epoxy adhesive. C. Protect concrete from damage. Exclude traffic from pavement for at least 14 days after placement. When construction traffic is permitted, maintain pavement as clean as possible by removing surface stains and spillage of materials as they occur. D. Maintain concrete pavement free of stains, discoloration, dirt, and other foreign material. Sweep concrete pavement not more than two days before date scheduled for Substantial Completion inspections. END OF SECTION Helaine K. Robinson CCS Senior Member Username: hollyrob Post Number: 141 Registered: 07-2003 Posted on Friday, May 20, 2005 - 09:34 am:    Dick, I think that we saw some on the UC campus during the tour at the May CSI meeting. You might want to call Joel Stout at UC. Richard L Matteo, AIA, CSI, CCS Senior Member Username: rlmat Post Number: 96 Registered: 10-2003 Posted on Friday, May 20, 2005 - 09:58 am:    You might also try the Portland Cement Association - they just put out a publication titled "Pervious Concrete Pavements" Portland Cement Association 5420 Old Orchard Road Skokie, IL 60077-1083 T-847.966.6200 F-847.966.9781 Ralph Liebing Senior Member Username: rliebing Post Number: 176 Registered: 02-2003 Posted on Friday, May 20, 2005 - 10:43 am:    And the 2004 MasterFormat number is ___________? Mark Gilligan SE, CSI Junior Member Username: markgilligan Post Number: 2 Registered: 05-2005 Posted on Friday, May 20, 2005 - 10:50 am:    I am new to the use of pervious concrete and I had a few questions reading the specification provided in a previous posting. The specification states that the sub-grade should not be compacted. Given the lack of reinforcing in pervious concrete, the performance of the slab will be greatly influenced by the sub-grade and the lack of compaction should lead to more cracking. The specification states that “aggregate, cement, water, and admixture per cubic yd. equal 27 cu.ft.”. If this is the case won’t all of this material fill all of the voids thus leaving no room for the necessary voids? Impervious liner and Drainage Pipe are listed in the specifications without any instructions for installation. How will the Impervious Liner be used if the intent of pervious concrete is to allow the free flow of water? I finally realized that the specification of the volume of voids is specified under Field Quality Control. Apparently the Georgia Concrete & Products Association recommends the use of ASTM C29 to test for voids and not ASTM C138. A Google search for “pervious concrete” found a number of references from concrete trade groups. Don Harris CSI, CCS, CCCA, AIA Senior Member Username: don_harris Post Number: 36 Registered: 03-2003 Posted on Friday, May 20, 2005 - 11:07 am:    Here's a link to a pdf document at PCA's site. I've never used it before, but it looks interesting. except... How does this function, if at all, in a freeze/thaw environment? Melting snow on top, running through the pores, refreezing below, heaving the sidewalk? Seems like this might be a Florida, So. California type of product. Is that true? http://www.cement.org/bookstore/profile.asp?store=&pagenum=1&pos=1&catID=&id=4091 Anne Whitacre, CCS CSI Senior Member Username: awhitacre Post Number: 203 Registered: 07-2002 Posted on Friday, May 20, 2005 - 03:12 pm:    Don: I've seen pervious concrete used in Seattle; it was precast into pavers, and then set on pedestals. It actually was BETTER in rain and snow/ice, because water doesn't stand on it, and snow melts through it, instead of staying slushy and then refreezing. The pavers were not slick when it was rainy, again because water doesn't stand on it. The first job I saw it on was done about 25 years ago and then it was sort of forgotten, and has become fashionable again. There are few suppliers, and even fewer who provide pavers, but I think its a terrific solution for climates that can have standing water. Joel Stout (Unregistered Guest) Unregistered guest Posted on Friday, May 20, 2005 - 05:14 pm:    Pervious or permeable paving comes in several forms including concrete, asphalt and unit pavers. For those in the Cincinnati, Ohio area there is a good location to see all of those types installed together in one place. The Northern Kentucky Sanitation District #1 in Ft. Wright, KY has recently completed a building addition and site development featuring several stormwater best management practices. These are smaller demonstration-type installations for the purpose of evaluation. Their building addition has an 'extensive green roof' (shallow soil vegetated roof system). Design team: Humpert Wolnitzek Architects and Human Nature Landscape Architects. Sanitation District No. 1 1045 Eaton Drive Ft. Wright, KY 41017 859/578-7450 At the University of Cincinnati the permeable paving system includes concrete pavers as the top layer. The paver shape creates voids which are then filled with aggregate that does not compact. Here's another explanation I was given for why freeze/thaw is not a big concern: The damaged caused by ice is from expansion during freezing. If water has not completely drained from the pervious paving system, the voids give the water space to expand into as it becomes ice. And, as someone else already mentioned, when snow and ice melt they have an open pathway to return to the aquifer rather than being held there for the next freeze cycle.