Deep foundation

File:Deep foundation drilling.ogg Deep foundation

A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does, to a subsurface layer or a range of depths. A deep foundation is used when there are weak soils near the surface or when the structure is very large and heavy, requiring a more stable and secure base.

Types of Deep Foundations

There are several types of deep foundations, including:

• Pile foundation
• Drilled shaft
• Caisson
• Screw pile
• Micropile

Pile Foundation

A pile foundation is a long, slender column made of materials such as concrete, steel, or timber, driven into the ground to support a structure. Piles are used to transfer the load of a building to a deeper, more stable soil layer.

Drilled Shaft

A drilled shaft, also known as a drilled pier or caisson, is a deep foundation that is constructed by drilling a hole into the ground and filling it with concrete. Drilled shafts are used for large structures and can carry very high loads.

Caisson

A caisson is a watertight retaining structure used in the construction of deep foundations. Caissons are used in underwater construction or in areas where the soil is unstable.

Screw Pile

A screw pile is a type of deep foundation that consists of a steel shaft with helical plates, which is screwed into the ground. Screw piles are used for both temporary and permanent foundations.

Micropile

A micropile is a small-diameter, high-capacity deep foundation element that is typically used in areas with restricted access or where minimal vibration is required. Micropiles are often used for underpinning existing structures.

Applications

Deep foundations are used in a variety of applications, including:

• Skyscraper
• Bridge
• Offshore platform
• Wind turbine
• Dam

Advantages

The advantages of deep foundations include:

• Ability to support heavy loads
• Stability in weak or variable soil conditions
• Suitability for a wide range of structures

Disadvantages

The disadvantages of deep foundations include:

• Higher cost compared to shallow foundations
• Longer construction time
• Need for specialized equipment and expertise

Related Pages

• Foundation (engineering)
• Geotechnical engineering
• Structural engineering
• Soil mechanics
• Construction