Why Does Concrete Settle?
Poor drainage, bad site conditions, and unwanted tree roots are some of the reasons why concrete may settle. The most common reason is when rainwater or water from your gutters washes away dirt from under the sidewalk or driveway. This creates a void under the concrete surface, which causes it to settle.
Another reason why concrete may settle is due to clay-rich soil. The soil expands and retracts as per the amount of moisture in it. When the soil is saturated with water, it expands. Then, when the soil dries, it shrinks. This instability in the soil causes the concrete to move and settle.