How is the Burj Khalifa built on sand?
The Burj Khalifa is held up by friction between its foundation and the sand.
While most skyscrapers rest on solid rock, the Burj Khalifa sits on deep soil. Its foundation uses 192 concrete piles driven 164 feet into the ground. These piles stay stable using 'skin friction,' which is the intense grip between the sand and the concrete surface. This friction supports the building's massive 500,000-ton weight.
Nerd Mode
The Burj Khalifa stands at 2,717 feet and weighs approximately 500,000 tons. Unlike many supertall structures that anchor into bedrock, the geology of Dubai consists of relatively weak calcarenite and siltstone. To support such a massive load, engineers from Skidmore, Owings & Merrill designed a specialized 'piled raft' foundation system.The foundation consists of a solid concrete mat that is 12.1 feet thick and contains over 58,900 cubic yards of concrete. This raft is supported by 192 high-performance reinforced concrete piles. Each pile is 5 feet in diameter and extends 164 feet deep into the ground. These piles do not rest on a hard surface but instead rely on the principle of skin friction.Skin friction is the resistance developed between the surface of the pile and the surrounding soil. As the weight of the tower pushes down, the pressure creates an immense grip between the concrete and the sand. This friction is so powerful that it prevents the piles from sinking further into the earth. To ensure durability, the concrete was mixed with a cathodic protection system to prevent corrosion from the highly corrosive groundwater in the region.
Verified Fact
FP-0001943 · Feb 16, 2026