Resources for Civil & Structural Engineers
Members Login
mec
engineers
FREE Engineering Articles
Home About Us Services Jobs Post-It Contact Us
 

Foundation Design - Types of Foundations

Foundation Design can be divided into Two Groups- Piled and Unpiled.

View Sketch for Types of Foundations

Piled foundation

Piled foundation design is simply those where the building foundations require piles to be driven into the ground to act as end bearing, friction or a combination of both. The piles can be made of concrete, timber or steel. Common shapes are square, circular, hollow, custom
Piled foundations are most common as it tends to give more confidence to the design engineer. Common types of piled foundations are:-

  • Driven Piles
  • Jack-in Piles
  • Bored Piles

Piled Foundations are always associated with Pile Caps & Stumps, either individually or combined, which is basically a thickened slab designed using deep beam truss analogy. The purpose of the pile cap is to really take loads from upper columns and the ground beams. An enlarged pile cap & stumps will provide sufficient space for incoming ground beams and rebars, and the required number of piles. All piles are normally driven vertically, however incase of excessive horizontal forces, raking at 1:7 is possible.

Two important parameters in piled foundation are "rigidity" and "efficiency". Building foundations using piles would have a high degree of rigidity, which means less differential and total settlement giving more stability, and reliability to building structures. On the other hand, costs could be higher due to inefficiency of pile groups in friction piles.   

Unpiled Foundation Design (Bearing Foundation)

This is simply those building foundations where piles are not used. They can also be termed as bearing foundations. They depend solely on the bearing capacity of the soil or rock to carry the load safely. Common types of such foundations are:

  • Isolated Pad footing
  • Combined Pad footing
  • Strip Footing
  • Raft and Basement Footing
  • Mass Foundation

Bearing foundation design are most common where the ground is a cut area, or of exposed rock, or where the soil is known to be stable and firm enough. Building foundations designed using this system should be more tolerable to differential and total settlement, such as lighter single storey buildings, timber buildings. In some cases due to difficulties in using a piling rig either constraint by existing structures or local regulations, or sound and vibration constraints, pad foundations would have to be used.

Next we will discuss on How Choosing Foundation Types --->

We welcome all comments and enquiries- Contact Us. Subscribe to our Free Newsletters on Engineering Designs

Authur- Philip Goh (B.Sc, MIEM, P.Eng. MICE, C.Eng)
MEC Engineers, Civil & Structural Engineer
Email:   

 

To Order
Design EBooks
Contact Us

 
 Calculations & Worked Examples for Design of Drainage System.

 Drainage Calcs

 Calculations for Design of Water Reticulation System

 Water Supply

 Calculations for Design of Circular RC Water Tanks

RC Water Tanks

-----------------

 

Authur- Philip Goh (B.Sc, MIEM, P.Eng. MICE, C.Eng) MEC Engineers, Civil & Structural Engineer HP: 016-8672189, Email: Widget: email cloaker