1. Shallow Foundations:

a. Isolated Spread Footing:

• The most common and economical shallow foundation type.

• Used for lightweight structures (typically up to five stories).

• Each column has its individual footing directly at its base.

• Transfers concentrated loads from columns to the soil.

   

b. Combined Footing:

• Supports multiple columns sharing a common footing.

• Used when individual footings would overlap or when soil bearing capacity varies.

• Ensures uniform load distribution.

   

c. Strip Foundation:

• A continuous footing along the length of a wall.

• Suitable for load-bearing walls or closely spaced columns.

• Distributes the load evenly to the soil.

   

d. Raft or Mat Foundation:

• Covers the entire area under a building.

• Ideal for heavy structures or poor soil conditions.

• Spreads the load uniformly over a large soil area.

   

2. Deep Foundations:

a. Pile Foundation:

• Consists of vertical piles driven into the ground.

• Used when shallow soil is weak or unstable.

• Transfers loads to deeper, more stable layers.

   

b. Pier Foundation:

• Similar to pile foundation but with larger-diameter columns (piers).

• Supports heavy structures like bridges and piers.

• Resists lateral forces and provides stability.

   

c. Caisson Foundation:

• Also known as drilled shafts.

• Constructed by drilling holes and filling them with concrete.

• Used for tall buildings, bridges, and offshore structures.

   

Remember, the choice of foundation depends on soil conditions, load-bearing capacity, and economic feasibility. Each type serves a specific purpose, ensuring the safety and durability of our built environment. 🏗️💪