Geoscience Reference
In-Depth Information
Soil foundations
21.1 Techniques for foundation treatment
•
The soil foundation supports structures such as rigid concrete footings for a build-
ing or an embankment for a road. Techniques for fill loading are covered in the
table below.
•
The foundation soil may often require some treatment prior to loading.
Table 21.1
Dealing with problem foundation grounds with fill placed over.
Improved by
Specific methods
Reducing the load
•
Reducing height of fill
Use light weight fill
•
Replacing the
•
Removal of soft or problem materials. Replace with suitable
problem materials
fill/bridging layer
with more competent
Bridging layer may be a reinforced layer
•
materials
Complete replacement applicable only to shallow depths
(3 m to 5 m depending on project scale)
•
•
Partial replacement for deeper deposits
Increasing the shear
Preloading
•
strength by inducing
•
Surcharging
consolidation/
Staged loading
•
settlement
Use of wick drains with the above
•
Vacuum consolidation
•
For predominantly granular materials: vibro - compaction, impact
compaction, dynamic compaction
•
Reinforcing the
Berms or flatter slopes for slope instability
•
embankment or its
•
Sand drains, stone columns
foundation
Lime and cement columns
•
Grouting
•
•
Electroosmosis
Thermal techniques (heating, freezing)
•
•
Geotextiles, geogrids or geocells at the interface between the
fill and ground
Transferring the
Pile supported structures such as bridges and viaducts
•
loads to more
Load relief piled embankments
•
competent layers
Search WWH ::
Custom Search