# Foundation Design: Theory and Practice

## Foundation Design: Theory and Practice

Foundations are essential to transfer the loads coming from the superstructures such as

buildings, bridges, dams, highways, walls, tunnels, towers and for that matter every engineer-
ing structure. Generally that part of the structure above the foundation and extending above the

ground level is referred to as the superstructure. The foundations in turn are supported by soil
medium below. Thus, soil is also the foundation for the structure and bears the entire load
coming from above. Hence, the structural foundation and the soil together are also referred to as
the substructure. The substructure is generally below the superstructure and refers to that part
of the system that is below ground level. Thus, the structural foundation interfaces the
superstructure and the soil below as shown in Figures 1.1 and 1.2. The soil supporting the
entire structure above is also referred to as subsoil and/or subgrade. For a satisfactory
performance of the superstructure, a proper foundation is essential.
The manmade superstructures or facilities/utilities are expected to become very intricate and
complex depending on creativity, architecture and infinite scope in modern times. However, the
soil medium is mother earth which is a natural element and very little can be manipulated to
achieve the desirable engineering properties to carry the large loads transmitted by the
superstructure through the interfacing structural foundation (which is usually referred to as
the foundation).

The book consists of 12 chapters plus appendices. Chapters 1–3 present the engineering
properties, tests and design parameters needed for the analysis and design of foundations.
Chapter 4 discusses the conventional and rational approaches for designing different types of
shallow foundations, including rafts. Methods for exact solutions using beams and plates on
elastic foundations are presented in Chapter 5. Numerical methods of analysis such as finite
difference method (FDM) and methods of weighted residuals (Galerkin, least squares, etc.) are
discussed in Chapter 6. The finite element method (FEM) for foundation analysis is explained
in Chapter 7. The design criteria for shallow foundations are presented in Chapter 8 while
actual design principles are given in Chapter 12 along with structural design details. Chapter 9
discusses the design and construction of deep foundations such as piles, large diameter drilled
piers, pile raft systems and non-drilled piers/caissons. The construction aspects and design of
pile foundations are presented in Chapter 10. The principles of machine foundation design are
discussed in Chapter 11. Chapter 12 summarizes the important provision of RCC design codes
and comparative features of commonly used codes such as the Indian Code, Euro Code, and
ACI Code. As mentioned earlier, detailed examples of structural design of shallow foundations
are also given in this chapter.