groundstructure

Ground structure is a term used in civil engineering and architecture to describe the foundational structural system that transfers loads from a building or other structure into the surrounding ground. It forms the lower portion of the structure, often referred to as the foundation or substructure, and is designed to ensure stability and limit settlement. The ground structure includes the physical elements that connect the superstructure to the soil: foundations, footings, grade beams, basement or crawl-space walls, piles or caissons, and the surrounding soil-structure interface. Proper design accounts for soil bearing capacity, settlements, groundwater, frost, and potential seismic or wind forces, as well as construction considerations such as waterproofing and drainage.

Foundations are broadly categorized as shallow or deep. Shallow foundations carry loads near the surface and include footings, strip or pad, and raft/slab-on-grade systems. Deep foundations transfer loads to deeper soil or rock and include piles (framed or driven), drilled shafts (caissons), and piers, often used in poor soils or for high-capacity structures. In some projects, the ground structure also comprises basements or sub-grade spaces that function as part of the foundation and provide service conditions such as storage and utilities.

Design begins with site investigation and geotechnical analysis to determine soil properties, groundwater, and environmental factors. Engineers select an appropriate foundation type, size, and reinforcement to achieve acceptable safety margins, limit differential settlement, and provide a reliable load path to the ground. Construction practices, drainage, and soil stabilization may be employed to improve bearing capacity or manage settlement.

Ground structure design interacts with other building systems and is a critical factor in long-term performance, durability, and resilience. While the term may be used flexibly, it is commonly synonymous with the foundation and substructure in modern engineering practice.