Durability Testing of Prefabricated Pervious Concrete Pavers

Pervious concrete pavements have received increasing research attention because of their potential to improve stormwater runoff management in urban environments. Since they are usually exposed to low temperatures during the winter period, it is important to test their durability in a cold climate. Existing protocols for testing of the frost resistance of ordinary concrete are not completely suitable for this type of material, particularly for prefabricated pervious concrete pavers. The frost resistance of pervious concrete pavers designed with partial replacement of cement with fly ash (10 and 20%) was tested with and without the presence of de-icing salts. Two exposure conditions were used: specimens were either sealed in plastic foil to prevent drainage during cycling or were allowed to drain. Each freeze–thaw cycle lasted 24 h. After every seven cycles, specimen mass and ultrasonic pulse velocity were measured; the specimens were then rewetted and testing continued. At the end of the test, the specimens were dried and their flexural and compressive strengths were determined. The results indicate that ultrasonic pulse velocity is sensitive to changes in the properties of pervious concrete. The proposed method therefore shows promise for further development and application.