Is Pervious Concrete Strong Enough?
Thus far it has been difficult to quantify the strength of pervious concrete. We have installed thicknesses of 6" through 10", and have found that with the correct mix and placement it has lasted for many years. We offer a 10 year limited warranty.
Ultimate endurance of Pervious Concrete is dependant upon a well compacted porous base, fast, but controlled placement, uniform compaction and correct control joints. These factors control raveling and cracking. (At present Pervious Concrete is not recommended for high speed, high traffic roads.)
To understand why Pervious Concrete is so strong, consider that the aggregate used is crushed, not round. This means that under compaction there is more contact between surfaces. The voids are like a honeycomb that creates unusual structural strength. And finally, it is believed that a chemical bond forms between the silicates in cement, some of which are part of its limestone component, and the chemicals in lime rock. (River gravel is not a suitable aggregate in pervious concrete.) Also, since lime rock is somewhat porous it allows penetration by the cement paste. We have more than 25 years working experience with Pervious Concrete, that is why we know it stands up when properly engineered and installed for its intended end use.
Properly installed pervious concrete as shown on the right will resist raveling, provide much greater strength and will last. The work on the left by a competitor was not properly screened and compacted.
New Possible Applications For Pervious Concrete
Airport Tarmac and Terminal Edge Strips. So much rain water is converted to storm water at airports because of the vast amount of paving for runways, ramps, tarmacs and gate areas. If some of that can be paved with Pervious Concrete, much rain water will reach the aquifer.
Curbs, Gutters and Bicycle Path Strips. This is a way that could divert a tremendous amount of water from the storm water sewers. Consider: A 3' wide by 150' long strip of pervious concrete upstream from a catch basin could return over 25,000 gallons of water per hour to the aquifer, diverting it from surrounding bodies of water. This estimate is based upon percolation rate of 1 gallon per minute per square foot.
Playground Bases. A well constructed Pervious Concrete system covered with shredded tire mulch can provide a well drained easily maintained playground surface.
Drainage Ditch Linings.
Sound Absorption Walls For Highways.