The Burj Khalifa is so heavy that it causes the ground beneath it to sink slightly.

The Burj Khalifa weighs approximately 450,000 to 500,000 metric tons when empty. This immense mass exerts significant pressure on the underlying geological strata of Dubai, which consists of weak sedimentary rock—specifically calcisiltite and sandstone—materials prone to compression under heavy loads.To prevent catastrophic sinking or tilting, engineers from Skidmore, Owings & Merrill designed a massive "piled raft" foundation system. It consists of a solid concrete mat 3.7 meters thick, supported by 192 bored reinforced concrete piles. Each pile measures 1.5 meters in diameter and extends 50 meters deep into the ground. This design increases the surface area to distribute the load and leverages skin friction against the soil to support the weight.During and after construction, the ground underwent settlement—a predictable compression process. Geotechnical sensors monitored this movement to ensure it remained within the predicted range of 45 to 80 millimeters. While the tower did cause the ground to sink slightly, the foundation system successfully managed this settlement, maintaining the structural integrity of the world's tallest building.