Chapter 7: Foundations and retaining structures

Foundation design, particularly for cases in which there is potential for earthquake loading, is usually carried out by geotechnical specialists. However, the building designer also needs to have an understanding of the issues affecting foundation design that are discussed in this chapter, as well being aware of the soil analysis issues that were discussed in Chapter 6.

This chapter covers

Life-threatening collapse of structures due to foundation failure in earthquakes is comparatively rare, even in the extreme circumstance when soil liquefaction occurs. This is because failure of the foundation limits the amount of shaking that is transmitted into the superstructure; it is a type of uncontrolled base isolation. Foundation failure accompanied by catastrophic collapse of the superstructure, therefore, does not often occur. However, foundation failures can be extremely costly; for example, liquefaction-induced failures in the port of Kobe, Japan, in 1995 are estimated to have cost many billions of pounds of structural damage, with a roughly equal loss arising from the economic consequences of the port’s closure.