What is the difference between pad foundation, strip foundation and raft foundation?Posted in Concrete Engineering, Piles Engineering | Email This Post |
Shallow foundation is commonly accepted as foundation with founding level less than 3m from ground surface. In case surface loads or surface conditions could still affect the bearing capacity, the foundation which sits on it is called shallow foundation.
Pad foundation refers to the foundation which is intended for sustaining concentrated loads from a single point load such as structural columns.
Strip foundation is used to support a line of loads such as load-bearing walls. For instance, closely-spaced columns render the use of pad foundation inappropriate and strip foundation may be a better alternative.
Raft foundation consists of a concrete slab which extends over the entire loaded area so that loads from entire structure are spread over a large area leading to a reduction of the stress of foundation soils is reduced. Moreover, raft foundation serves to avoid differential settlement which otherwise would occur if pad or strip foundation is adopted.
This question is taken from book named – A Closer Look at Prevailing Civil Engineering Practice – What, Why and How by Vincent T. H. CHU.