Solution:

• Grillage foundation consists of one, two or more tiers of steel beams superimposed on a layer of concrete.
• It is a foundation system that consists of closely spaced beams, usually placed in two perpendicular directions, forming a grid-like pattern.
• It is used to distribute heavy loads from columns or walls to the underlying soil in situations where individual footings might be inadequate.
• Grillages are particularly useful when dealing with uneven or variable soil conditions.
• Its provided at the base of the column itself.
• Its generally provided as at a shallow depth when compared to its width.