Download - Underpinning Presentation
PURPOSE OF PURPOSE OF UNDERPINNINGUNDERPINNING
Underpinning on an existing building or other structure is the process of ;
- Strengthening - Stabilizing the Foundation
CONSIDERATIONS BEFORE UNDERPINNING
• Height of the building
- Types of underpinning should be able to receive load, according to the height of the building.
• Column spacing & Wall thickness - Column & Wall above the affected footing
should be braced as much as possible• Type and material of construction - Used of underpinning types & material should
have quality• Condition of the building - To make sure the actual problem and to find
out the suitability of the installation. 3
Types & Suitability Of UnderpinningTypes & Suitability Of Underpinning
a) The types of underpinning include various systems of piers and piles, such as :
Jacked piles, screw piles, Bracket piles and mini-piles helical piers
b) The types of piers and piles differ according to the installation process, other materials used for underpinning and the layout of the piers or piles.
Jacked piles
It’s use when the existing structure
underlain by collapsible soils
(e.g. granite), and compressible clays.
Screw pile -Screw piles are steel screw-in-pilling
& ground anchoring system used
for building foundations.
Bracket Piles A steel H pile driven next to an existing foundation. A steel bracket is welded to the pile & extends under & support s the foundation
Micro piles Micro piles, also called Mini-piled is generally existing when the loads from the foundations need to be transferred to stable soils at considerable depths - usually in excess of 5.0 meters.
Helical PierInstallation of the foundationsupport works helical pier system is uniquely suited for both heavy & light structure.