A foundation is a structure that transfers loads to the ground. Structure is a fundamental and sometimes Intangible notion covering the Recognition, Observation, nature, and Stability of Foundations are generally broken into two categories: shallow foundations and deep foundations. A shallow foundation is a type of foundation which transfers building loads to the earth very near the surface rather than to a subsurface layer or a range of depths as does A deep foundation is a type of foundation distinguished from Shallow foundations by the depth they are embedded into the ground
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Shallow foundations
Shallow foundations are usually embedded a meter or so into soil. A shallow foundation is a type of foundation which transfers building loads to the earth very near the surface rather than to a subsurface layer or a range of depths as does Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel One common type is the spread footing which consists of strips or pads of concrete (or other materials) which extend below the frost line and transfer the weight from walls and columns to the soil or bedrock. The frost line —also known as frost depth or freezing depth —is most commonly the depth that the Groundwater in Soil is expected Another common type is the slab-on-grade foundation where the weight of the building is transferred to the soil through a concrete slab placed at the surface. Concrete is a construction material composed of Cement (commonly Portland cement) as well as other cementitious materials such as Fly ash and Slag
Deep foundations
Deep foundations are used to transfer a load from a structure through an upper weak layer of soil to a stronger deeper layer of soil. A deep foundation is a type of foundation distinguished from Shallow foundations by the depth they are embedded into the ground There are different types of deep foundations including piles, drilled shafts, caissons, piers, and earth stabilized columns. The naming conventions for different types of foundations vary between different engineers. Historically, piles were wood, later steel, reinforced concrete, and pre-tensioned concrete. Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 Reinforced concrete is Concrete in which reinforcement bars (" Rebars quot or fibers have been incorporated to strengthen a material that would otherwise be Prestressed concrete is a method for overcoming the Concrete 's natural weakness in tension. Sometimes these foundations penetrate bedrock. Bedrock is the native consolidated rock underlying the surface of a terrestrial planet usually the Earth.
Design
Foundations are designed to have an adequate load capacity with limited settlement by a geotechnical engineer, and the foundation itself is designed structurally by a structural engineer. Geotechnical engineering is the branch of Civil engineering concerned with the engineering behavior of earth materials Structural engineers analyze design plan and research structural components and Structural systems Their work takes account mainly of technical economic and environmental
The primary design concerns are settlement and bearing capacity. Consolidation is a process by which Soils decrease in volume It occurs when stress is applied to a soil that causes the soil particles to pack together more tightly In Geotechnical engineering, bearing capacity is the capacity of soil to support the loads applied to the ground When considering settlement, total settlement and differential settlement is normally considered. Differential settlement is when one part of a foundation settles more than another part. This can cause problems to the structure the foundation is supporting. It is necessary that a foundation is not loaded beyond its bearing capacity or the foundation will "fail".
Other design considerations include scour and frost heave. Frost heaving (or frost heave) occurs when Soil expands and contracts due to freezing and thawing Scour is when flowing water removes supporting soil from around a foundation (like a pier supporting a bridge over a river). Frost heave occurs when water in the ground freezes to form ice lenses.
Changes in soil moisture can cause expansive clay to swell and shrink. Expansive clay is a Clay that is prone to large volume changes that are directly related to changes in Water content. This swelling can vary across the footing due to seasonal changes or the effects of vegetation removing moisture. The variation in swell can cause the soil to distort, cracking the structure over it. This is a particular problem for house footings in semi-arid climates such as South Australia, Southwestern US, Turkey, Israel, Iran and South Africa where wet winters are followed by hot dry summers. Climate encompasses the temperatures humidity rainfall atmospheric particle count and numerous other meteorogical factors in a given region over long periods of South Australia is a state of Australia in the southern central part of the country The Southwestern area of the United States could be defined as the states west of the Mississippi River, with the qualification of a certain northern limit such as the 37 Turkey (Türkiye known officially as the Republic of Turkey ( is a Eurasian Country that stretches For a topic outline on this subject see List of basic Israel topics. For a topic outline on this subject see List of basic Iran topics. The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa Raft slabs with inherent stiffness have been developed in Australia with capabilities to resist this movement.
When structures are built in areas of permafrost, special consideration must be given to the thermal effect the structure will have on the permafrost. This article is about frozen ground For other meanings see Permafrost (disambiguation. Generally, the structure is designed in a way that tries to prevent the permafrost from melting.