A British materials solution company has been developing a new form of concrete capable of absorbing far more water than standard concrete. Tarmac has been developing its product Topmix Permeable for the last six years. While standard concrete abosorbs around about 300 mm of water per hour, Topmix is capable of absorbing 880 gallons of water per minute, equivalant to 36,000 mm. Topmix is not a sand based concrete, instead it uses much larger pieces of crushed granite that allow for more drainage space between “particles”. Topmix has performed best in areas with a speed limit under 30 mph with light to medium traffic, but has not done well in colder climates.
First off, Topmix certainly has the potential to benefit certain areas of the world, such as those that receive high amounts of rainfall or have general problems with roadways becoming subject to floods. However, the product’s expensive upfront investment may hinder its ability to be used in parts of the world that need it most, such as certain areas of India affected by annual monsoons. So perhaps Topmix is not necessarily meant to be a replacement for an existing product, but a new product that can pioneer its own applications.
Topmix may not be feasible for many roadways due to high cost and low traffic speed, but it certainly could be used in many other applications such as parking lots, bicycle paths, and outdoor sport courts. This could open doors to allow cyclists to ride in all kinds of weather, or allow a basketball game to be played during a downpour.