Problems caused by acid rain and smog inducing nitrogen oxides (NOx) from the backsides of cars may soon be in the rearview mirror thanks to a new type of concrete.
One bustling road was singled out in the bustled of Henglo, The Netherlands, as the perfect place for Dr. Jos Brouwers of the Eindhoven University of Technology to test out the claims of air-purifying concrete slabs currently being produced by paving stone manufacturer Struyk Verwo Infra.
1000 square meters of standard surface were ripped out of the well-travelled Castorweg Road and replaced with the new concrete mix, while a 1.000 square meter chunk was left "as-is" for comparison purposes.
Then, Dr. Brouwers - a professor of building materials at the University - sat back and watched the magic happen.
More accurately, he let a bunch of cars drive over this new pavement and then did what scientists do best: measure stuff. And, since he is a professor of building materials, he was very careful, detailed, and through with his measurements.
His measured conclusion? That the stuff actually works.
Tests conducted between one half and one and a half meters above the new road surface showed a 25 to 45 percent drop in NOx levels compared to those above the control section. Huzzah!
NOx: Don't eat it.
As it turns out, the concrete contains titanium dioxide, which grabs the NOx as cars driving above spit it out their tailpipes. With the help of everyone's favorite celestial object, the sun, this titanium dioxide converts the NOx into harmless nitrates that are washed off of the road surface by rain. This lack of NOx means a lack of noxious smog and acid rain, which is good for the environment, asthmatic individuals, and anyone who wants to walk out in public without having their clothing shredded by a stinging water shower of death.
Ok, so acid rain can't do that. Yet. But it's still bad, and this concrete gets rid of it. What more do you want here?
Up until the Henglo test, the properties of this concrete had only been demonstrated in a lab, and knowing the mixture can work outdoors where cars actually operate is a big step forward.
The new concrete does cost more than the traditional form, in the order of 50% more, but still results in the overall cost of road building being only 10% higher. How that works out exactly, we're not sure - perhaps it's some form of new Dutch math.
In addition, the concrete can be mixed in with standard asphalt for roadways in which that would be preferable, meaning that almost anywhere that there are cars, there can be a way to clean up their waste.
As an added bonus, the hungry concrete is also sated by algae and dirt, and so stays clean and pristine.
Not bad for a giant slab of car toilet.
Source: Eindhoven University of Technology