We’re not talking about heaving chunks of concrete like the Incredible Hulk here. Unfortunately, the subject is a little less exciting than that and concerns heaving sidewalks in a commercial paving capacity.
There are many different reasons that a slab of concrete can and will heave in inconvenient locations. Not that any location is convenient, it’s just that some of the reasons are easier to effect a concrete repair by a commercial paving contractor than others. In virtually all the cases of heaving sidewalks, it is the underlying structure that is the issue and not the concrete itself. Sure, concrete can shrink and expand, but not to the degree that it will heave all on its own.
Poor drainage can explain the majority of the instances of heaving sidewalks. Water can erode a mountain given enough time so it isn’t a stretch to see how a little water with a dash of winter can erode the ground beneath a concrete slab. The unstable concrete slab then starts to tilt and shift. Poor drainage and a sub-par foundation is the cause. The solution provided by a commercial paving contractor could either be to life the slab and fix the ground beneath it and reset the slab or it may require the slab to be broken up, removed, and re-poured.
The roots of trees can also be a big factor when it comes to heaving sidewalks. If a tree is too close to the sidewalk, as it continues to grow, the root structure can easily push the concrete up. It isn’t a matter of concrete repair, but a dilemma of what to do with the tree. You can leave it there and re-route the sidewalk or get rid of the tree. Unfortunately, at that point the tree is most likely too big to transplant and simply must come down. There are many reasons that sidewalks will heave, contact a professional commercial paving contractor to assist you in figuring out the best way to remedy the situation.