Sustainable design of pervious concrete pavements

This research evaluated the performance of a waste-incorporated pervious concrete pavement (PCP) system in Denver, Colorado. This dissertation provides recommendations for designing and constructing PCP in the unique Colorado environment of fluctuating temperatures, low humidity, and frequent freeze/thaw conditions.A PCP system functions both as a stormwater detention system and as a pavement surface and must therefore meet specific hydrological and structural performance criteria. Preliminary laboratory testing evaluated the spectrum of mixture design recommendations and established a base mixture design to exceed these performance criteria. Subsequent phases of laboratory testing modified this base mixture design with fly ash, fine aggregate, and air-entraining admixture to establish acceptable limits for each. Some mixtures exhibited a distinct region of imperviousness. The use of hydration stabilizing admixture prevented this phenomenon and was therefore recommended.A PCP test section was constructed on the Auraria Campus of the University of Colorado Denver. This test section was completed in a parking lot and utilized 20% fly ash replacement for cement in the PCP mixture, crushed recycled concrete as the underlying coarse aggregate, and 10% replacement of sand with crushed glass in the fine aggregate layer. Testing of the PCP test section confirmed that the structural and hydrological requirements were met.Subsequent field investigations included monitoring of the PCP test section for reduction in the heat-island effect, water quality, deterioration, clogging, and permeability. The water quality analysis demonstrated that the waste-incorporated PCP system was effective in filtering heavy metals and chlorides however, it produced an alkalinic solution.An examination of the suspected causes of PCP deterioration prompted an investigation into the effect of deicing agents. Results demonstrated that deicers strip the important cement binding paste from aggregate particles and thus contribute to the accelerated deterioration of PCP. The remainder of the suspected failure mechanisms were evaluated within the aforementioned phases of laboratory and field testing.This research confirmed that sustainable PCP can be placed in the semi-arid climate of Denver. Correct construction details were critical to the performance of the pavement. Specific mixture design, placement, and curing recommendations resulted from this research.