There are different types of footings that are often used in building construction, and depending on their depth, they can be deep or shallow footings.
In its most basic form, footing refers to the expansion of the base of a column or wall to distribute weight on the supporting soil.
Footings are structural components used to support columns and walls when the soil’s load-carrying capability is low.
The differential settling is maintained, as is enough protection against overturning or slipping.
Basic footing design requirements:
A site investigation is required in order to determine the chemical and physical properties of the soil.
- Determine the amount and distribution of superstructure loads.
- Determine the best and most cost-effective foundation.
- Determine the excavation method and footing depth.
- Identify the maximum bearing pressure that can be used in the design.
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Types of Footing
Combined footing – A combination footing is one that supports two or more columns. It is utilized when two or more columns are near to each other or when two or more individual column footings would overlap. The plan of a combined footing might be trapezoidal or rectangular. When one column’s load exceeds that of the other, a trapezoidal footing is provided.
Combined footings are used to transmit loads from closely spaced columns to the ground or when the column faces the plot border.
Isolated footing – One of the most common foundation types for supporting single-column arranged at a distance is an isolated footing. The isolation footing’s design must avoid exceeding its bearing capacity, provide protection against overturning or sliding, and prevent ground subsidence.
Mat or raft foundation – A mat foundation is a continuous slab laid on the ground that supports and transmits the structure’s weight to the ground. It helps in the alleviation of soil stress
Sloped footing- Sloped or trapezoidal footings are carefully designed and built to maintain a top slope of 45 degrees from all sides. The sloping footing structure uses less reinforcement and concrete than the plain, isolated footing. As a result, it reduces the need for concrete and reinforcement.
Stepped footing – These types of footings were poured at different heights. Although this footer fluctuates in height with the ground, a complicated one appears as a series of steps. That is why it is called a “step footer.”
Strapped footing – It’s a type of composite footing made up of two or more column footings joined by a concrete beam. In a construction foundation, it is used to help distribute the weight of a heavily loaded or eccentrically loaded column footing to adjacent footings.
Wall footing/strip footing – These footings are used to support both structural and non-structural walls. The footing under the wall is thin and continuous.