Every sturdy structure is supported by a strong foundation that relies on the ground on which it rests. Whether it is a house, a commercial building, or any other infrastructure, it is safe to assume that the building is standing upright due to the reinforcement secured underground. The foundation is a crucial feature of a structure and any construction project needs to establish a suitable foundation to increase the strength and safety of the building.
The foundation of a building is the skeleton of a structure and a fickle one that lacks in durability will surely compromise the safety of those who will inhabit or utilize the building. Because of this, the creation of the building’s foundation during construction follows strict rules and regulations in order for the structure to be equipped with a strong foundation that is established firmly on the ground. Calculating the proper depth of a foundation before the construction of the building is a crucial step before anything else. In this article, we will discuss the formula you can use in order to calculate the depth of a structure’s foundation.
How to Calculate the Depth of a Building’s Foundation
Providing the most suitable depth of foundation for any structure is crucial for many reasons. A foundation established in proper depth will have enough structural support, stability, balance, and most importantly, safety. Because of this, construction professionals like civil engineers, geotechnical engineers, architects, and even construction managers properly calculate the depth of a building’s foundation to ensure that it will have the sufficient reinforcement it requires. To figure out the depth, construction professionals utilize the industry standard Rankine’s formula to determine how deep of a foundation a structure requires.
Image from The Constructor
Below is a sample formula.
Gross bearing capacity of soil = 300 kN/m2
Density of Soil = 18 kN/m3
Angle of repose = 30 Degrees
The minimum depth of the foundation = 1.85m
Sample formula by The Constructor.
Rankine’s Method for Foundation Estimation
Rankine’s method is used by construction professionals to determine the minimum depth of a structure based on the data collected on the location of the construction site, however, it is important to note that the method only provides an estimate of the depth. Multiple other factors such as the actual location and climate conditions of the construction site should be considered. In addition, the soil investigation should first be done before the estimation begins. This allows the project design to consider the actual bearing capacity of the soil, the water below ground that will scour the soil, and even the effects of another foundation in close proximity, if there is any.
The Importance of the Foundation
Any sturdy building stays upright due to a sturdy foundation. Allocating the proper depth for a foundation allows a building to be properly anchored underground. This increases the overall strength and longevity of the building. With the use of Rankine’s method, the proper depth of the foundation can be estimated, and construction professionals can provide the structure with proper support.
Mishra, G. (2014, November 12). How to Determine Depth of Foundation? The Constructor. Retrieved December 13, 2023, from https://theconstructor.org/geotechnical/determining-depth-of-foundation/9339/