You hate them. We hate them. They’re the bane of every vehicle owner – potholes! These nasty depressions in the roads may seem harmless to pedestrians, but they can cause millions, if not billions, of dollars in vehicular damage if left unchecked.
But how do these sneaky buggers even come to be?
Civil engineer Grady Hillhouse explains that potholes are inevitable due to the design of roads. Underneath most roads is a subgrade layer of native soil; whereupon a base course of flat rock lies. This base course provides the bedrock for the black asphalt you see every day.
This is the design being used by almost every country to create roads due to how cost-effective and efficient it is. But no matter how sturdy a material is, continuous exposure to elements is bound to take its toll.
It starts with cracks in the asphalt. As cracks begin to appear, holes leading from the surface to the base course and subgrade make it easy for water to accumulate underneath.
But that’s just one-half of the pothole-making process. Once the water goes in, vehicles pressing on the cracked asphalt push the water back out – carrying soil particles from the subgrade.Tthis also explains why you’re likely to find potholes in high-traffic areas.
As time goes on, the soil underneath the road begins to weaken and collapse. This pushes the asphalt down, creating the potholes you all know and loathe.
Grady goes on to say that roads in areas with icy weather are even more prone to potholes. Ice lenses are pockets of ice which form due to the expansion and freezing of the water underneath a road. Once the ice thaws out, an even bigger gap is left. This will then start a huge pothole.
To fix a pothole, roadway owners typically replace the missing soil and cover it up with new asphalt. This isn’t a full-proof solution, as they’re just using the temporary material to bandage what is broken.
There are a couple of better ways to fix these roads, such as thickening the asphalt or using sturdier materials like concrete. Nonetheless, doing so can significantly increase the cost.
There’s also the concept of maintenance. Since roads are constantly being bombarded by traffic and the weather, they have to be regularly maintained. This is one reason you pay your taxes. So, next time you’re driving and feel a bump because of a pothole, better call the attention of those in power by sending them this informative read!