The use of magnesium chloride deicer on pervious concrete may be harmful to its mechanical properties. However, carbonation of the cementitious materials might increase its resistance to MgCl2 attack. Previous studies evaluated the efficacy of using carbonate laden water, specifically sodium bicarbonate solution treatments on pervious concrete, to accelerate the carbonation process and perhaps increase the material’s resistance to MgCl2 impacts. In this paper, 43 pervious concrete cylindrical specimens were subjected to 2 5-day treatments with either a 3.3% concentrated NaHCO3 solution or tap water, as a control. After treatment the compressive strength, elastic modulus and ductility, were tested. For half the specimens these mechanical property tests were tested a few days after treatment, and for the other half the tests were conducted two months later. Therefore age after treatment became an additional independent variable. The NaHCO3 treatment seemed to decrease the early tested specimens’ compressive strength, but the same type of treatment appears to increase the material’s compressive strength values, if tested 2 months later. No statistically significant changes in elastic moduli or ductility were noted. These results might imply that the sodium bicarbonate treatment may need to be combined with a natural carbonation or aging process, even after the treatment application, in order to be effective in terms of gain in compressive strength, but more research is needed, especially in order to verify the effectiveness of the treatment with respect to the resistance to MgCl2 deicer attacks.

DOI: https://doi.org/10.1061/9780784483114.008

Early Treatment of pervious concrete with carbonate laden waters

The International Low Impact Development Conference highlights interdisciplinary practice, research, and implementation of Low Impact Development (LID), Green Infrastructure (GI), Sustainable Urban Drainage Systems (SUDS) and Water Sensitive Urban Designs (WSUD). The focus will be on using our past and present understanding of LID to tune management programs, design practice, and operation and maintenance into the future.