Have you ever played the game “Step on the crack, you’ll break your mama’s back?” Well, those cracks that you jumped over are caused by the sinking of concrete or lack of concrete stabilization. A lot is happening beneath our feet all the time and, when you stop to think about it, it is quite fascinating. Of the many possible causes of concrete shrinking, there are three main reasons: soil shifting, underground dwelling animals, and erosion or natural geological movement.
The soil beneath concrete can shift and move for various reasons – from geological movement near fault lines, diminished load capacity due to loosely packed soil to soil moisture – all of these contribute to lack of concrete stabilization. If concrete isn’t poured atop tightly packed, dry soil, cracks will form over time.
Unfortunately, humans have taken over the habitats of many animals as a by-product of industrialization. We have inadvertently caused our concrete to crack from gaps created in the soil beneath us. What creates these gaps? The furry residents in the underlying soil, of course. Various burrowing rodents that happen upon loose soil will create tunnels they call home. As previously mentioned, the compromised soil beneath concrete will create gaps and cracks due to shrinkage.
Concrete stabilization is jeopardized by even the most natural phenomena: weather erosion and geological shifting, from slight tectonic plate activity to major earthquakes. Perhaps the most incredible visual example of erosion is the Grand Canyon. Over thousands of years, the Colorado River gradually eroded the rock into one of the 7 Great Wonders of The World. On a more pragmatic note, sidewalk cracks are the most common example of erosion. Cracks in a house’s foundation are a particularly costly and dangerous result of concrete erosion.
There is so much more to think about while mundanely walking down the street! There may very well be a family of rodents scurrying about under your feet, creating a gap or crack that will give the children a few steps ahead of you a way to entertain themselves.