Each Building has two main components. The one component constructed above the ground level is known as super-structure while another component which is constructed below the ground level is called sub-structure. Foundation falls into the category of sub-structure.
Foundation is a Structural supporting member which transfer loads from the Building’s walls or Columns to the Earth. The loads from Slab, Beam, Column, wall etc. should be safely transferred to the Soil. The Substructure that is provided to transfer loads from the superstructure to the Earth is known as Foundation.
House Foundation System
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A foundation is the part of the building that is in direct contact with the ground. The main purpose of the foundation is to transfer the whole weight of the building to the ground.
The foundation selection will also depend on the structural system and type of the structure
Foundation is a general word, commonly known as ‘footings’. Usually, every building has an individual or combined footing for each column or multiple columns or walls of the building. It prevents the differential settlement by evenly loading substrata.
Foundations are generally built of Concrete, bricks, Steel, stones, etc. The type of foundation (like isolated footing, combined footing, strip footing, raft footing, pile footing etc ) and selection of material mainly depend on the type of the structure above and the underlying soil.
Since the weight of the building rests on the soil, experts need to study the properties of the soil very carefully to make sure that it can carry the load of the building. Geotechnical engineers after the soil investigation will provide the Safe Bearing Capacity (SBC) of soil where is the basic things we need and from the SBC value, the structural designer designing the building will decide the type and size of columns, beams, slabs, and footings. The images display the typical types (like square (pad), stepped and sloped footings) of isolated footings.
Courtesy - 123rf
A person buys or builds a house once in life-long only and foundation is very important as it is the basic foundation of the safety of the structure.