rockfoundation

Rock foundation refers to the solid bedrock or near-surface rock layer that underlies a structure and provides its primary bearing support. In engineering, locating bedrock is desirable because it offers higher shear and compressive strength than soil, reducing settlement and long-term movement. The depth to bedrock and its rock quality influence foundation design; projects may use shallow foundations resting directly on bedrock, or, when bedrock is deeper, deep foundations such as drilled shafts, rock sockets, or piles anchored into the rock.

Key factors include rock type, jointing, weathering, and the intact rock mass strength. Geotechnical investigations use boreholes, rock coring, and in-situ tests to determine bearing capacity, RQD, and rock mass rating. When bedrock is irregular or fractured, engineers may employ reinforcement or grouting, or choose alternative ground improvements.

Construction on rock foundations offers advantages such as reduced settlement and high load-bearing capacity, but can present challenges like variable weathering, groundwater flow, and the technical complexity of anchoring structures into rock. Maintenance considerations include monitoring for rock wedge movement, joint movement, and water-related deterioration.

Outside engineering, "rock foundation" can also refer to the underlying bedrock of a landscape or a geological concept describing the foundation of uplifted terrains. The term is less common as a formal technical category beyond bedrock or rock-based foundations.