Changes

Concerns over the resistance to the [[freeze-thaw]] cycle have limited the use of pervious concrete in cold weather environments.<ref name="Cold Weather">{{cite web|author1=Vernon R. Schaefer |author2=Keijin Wang |author3=Muhammad T. Suleiman |author4=John T. Kevern |title=Mix Design Development for Pervious Concrete in Cold Weather Climates |url=http://www.ctre.iastate.edu/reports/mix_design_pervious.pdf |publisher=Iowa State University |location= Ames, IA |year=2006}} National Concrete Pavement Technology Center. Report No. 2006-01.</ref> The rate of freezing in most applications is dictated by the local climate. Entrained air may help protect the paste like in normal concrete.<ref name="Entrained Air"/> The addition of a small amount of fine aggregate to the mixture increases the durability of the pervious concrete.<ref>{{cite journal |last=Kevern |first=John |author2=K. Wang |author3=V.R. Schaefer |journal=Iowa State University|year=2008}}{{full citation needed|date=November 2015}}</ref> Avoiding saturation during the freeze cycle is the key to the longevity of the concrete.<ref name="Concrete Tech">{{cite web|title=Pervious Concrete and Freeze-Thaw|url=http://www.cement.org/tech/Pervious_print.html |work=Concrete Technology E-Newsletter |publisher=PCA |accessdate=30 September 2012}}</ref> Related, having a well prepared 8 to 24&nbsp;inch (200 to 600&nbsp;mm) [[Grading (engineering)|sub-base]] and drainage will reduce the possibility of freeze-thaw damage.<ref name="Concrete Tech"/>

Concerns over the resistance to the [[freeze-thaw]] cycle have limited the use of pervious concrete in cold weather environments.<ref name="Cold Weather">Vernon R. Schaefer, Keijin Wang, Muhammad T. Suleiman, John T. Kevern, Mix Design Development for Pervious Concrete in Cold Weather Climates, , Iowa State University, Ames, IA, 2006 National Concrete Pavement Technology Center. Report No. 2006-01.mix_design_pervious.pdf</ref> The rate of freezing in most applications is dictated by the local climate. Entrained air may help protect the paste like in normal concrete.<ref name="Entrained Air"/> The addition of a small amount of fine aggregate to the mixture increases the durability of the pervious concrete.<ref>{{cite journal |last=Kevern |first=John |author2=K. Wang |author3=V.R. Schaefer |journal=Iowa State University|year=2008}}{{full citation needed|date=November 2015}}</ref> Avoiding saturation during the freeze cycle is the key to the longevity of the concrete.<ref name="Concrete Tech">{{cite web|title=Pervious Concrete and Freeze-Thaw|url=http://www.cement.org/tech/Pervious_print.html |work=Concrete Technology E-Newsletter |publisher=PCA |accessdate=30 September 2012}}</ref> Related, having a well prepared 8 to 24&nbsp;inch (200 to 600&nbsp;mm) [[Grading (engineering)|sub-base]] and drainage will reduce the possibility of freeze-thaw damage.<ref name="Concrete Tech"/>