Why Does Concrete Settle?
Some of the reasons why concrete settles are poor drainage, low-quality compaction, bad site conditions, and tree roots. The most common reason is when water from gutters or rain washes away dirt from under concrete surfaces like sidewalks or driveways. This creates voids or pockets beneath the concrete causing it to settle.
Another reason is clay-rich soil. The soil expands and contracts according to its moisture level. It expands when it’s saturated with water. Then when the soil dries, it shrinks. This makes the soil unstable, causing your concrete to move and sink.