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Review of Maryland SHA Specification for Portland Cement Concrete Permeable Pavement System. Maintenance. Freeze Thaw Durability. Abrasion Resistance. Strength. The American Concrete Institute Committee Report ACI 522R-Pervious Concrete, Chapter 7.2.2 states:
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Review of MarylandSHA SpecificationforPortland Cement ConcretePermeable PavementSystem
Strength The American Concrete Institute Committee Report ACI 522R-Pervious Concrete, Chapter 7.2.2 states: “Guidance for structural design of conventional concrete pavements is provided in ACI 330R for parking lots and in ACI 325.12R for streets and roads. These documents cover many different aspects of paving design. The structural design recommendations in these documents, however, are not necessarily applicable for use with pervious pavement. As there are no standardized test methods for strength of pervious concrete, design and specification by strength should be avoided”.
Testing Fresh DensityASTM C1688 Density and Void Content of Freshly Mixed Pervious Concrete • 0.25 ft3 measure (standard air pot) • Standard Proctor Hammer
Example Portland cement…….……...600 pcy Coarse aggregate*…..…...2,670 pcy (ssd) Water………………… …..180 pcy Total Weight…………......3,450 pcy *b/b 0 = 1.00 Dry rodded unit weight = 98 pcf Design plastic unit weight = 3,450/27 = 128 pcf Acceptance 128 +/- 5 pcf Design air-free unit weight = 163 pcf Calculated void content = (163-127)/163 = 22% > 15%
Fill in two equal layers 1st lift – 20 drops
ASTM C1701 Infiltration Rate as a Function of ASTM C1688 Void Content Kevern, J.T, Montgomery J
Measuring In Place Infiltration • ASTM C1701 • Infiltration Rate of In Place Pervious Concrete
Test Equipment Infiltration Ring – 12 +/- ½ in. Scale Container – 5 gallons Stop watch Plumbers Putty Water
Test Location • 3 test for up to 25,000 sft • Additional test for each 10,000 sft • Minimum 3 ft between test location • No standing water • Do not test within 25 hours of rain
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