|Sustainability has become one of the most important design factors for pavement engineers over the last several years. Much of this focus has been on reducing material costs for pavement infrastructure by using innovative materials into traditional pavement design. Pervious concrete pavement has the ability to offset the typical requirement for stormwater management ponds for large paved areas. It can be considered as an alternative to impervious pavement systems as the open void structure of pervious concrete pavement allows water to infiltrate very quickly through it and join the natural ground water table. As a result, it does not disturb the natural hydrological cycle or increase the demand on the local stormwater management. Besides stormwater management, pervious concrete can also provide environmental and economic benefits such as removing water pollutants, reducing noise pollution, lowering the heat island effect, lowering light demand, and increasing driver safety through improved visibility.
Pervious concrete pavement is receiving more and more interest recently due to the pressure by environmental agencies and environmental acts to reduce the quantity of stormwater runoff from urban areas. The introduction of pervious concrete pavements in cold weather climatic regions, specifically Canada, was driven by their sustainable benefits. However, there has been caution in the pavement industry to use pervious concrete in climates that experience freeze-thaw cycles. Literature shows that there is no dedicated test method to assess the performance of pervious concrete, which is structurally substantially different from conventional concrete pavements. The increased use of pervious concrete in roads, walkways, and parking lots demands improved specifications, performance criteria, and acceptance test methods for evaluating structural performance and durability of this innovative concrete product.
The main objective of this research is to recommend specifications and performance criteria for pervious concrete based on the results of experimental investigations and field experience in Ontario, Canada. Above all, this study attempts to establish test procedures for evaluation of durability and performance of pervious concrete pavement. Initially the test methods available for conventional concrete were performed, the gaps were identified and the test methods were modified. Field samples were also collected and the modified test methods were performed on the field cores to define correlation between the laboratory and the field samples.
Several pervious concrete field sites were constructed by the Centre for Pavement and Transportation Technology (CPATT) at the University of Waterloo, the Cement Association of Canada, and several other industry members from 2007 to 2011. Initial results from this work have been published previously. This research described herein involved continued collection of drainage data from instruments such as the moisture gauge measurements, strain gauge at three sites that are still being monitored. This field/laboratory study provides insight into the longer term drainage performance of pervious concrete pavement. This study has also involved an evaluation of the latest mix design, which has also built upon previous research. In addition new test methods have been evaluated and now that the pervious test sections are more than seven years old, the longer term drainage monitoring has been assessed.
Barriers to implementing this technology are being solved, as the research is assisting designers on the various functional and structural design aspects. In this research, a framework is also developed to identify how pervious concrete can be integrated into low-volume infrastructure for cold climate such as Canada.