Heavy loads where the bearing stratum is deep
When the upper soils cannot carry a structure's load, even after improvement, the load is transferred to deeper, stronger strata.
How it is recognised
- Column or equipment loads beyond the capacity of shallow foundations.
- A competent stratum or rock only at depth.
- Uplift or lateral loads on foundations.
Why it matters
Shallow foundations on inadequate ground settle excessively or fail in bearing; tall and heavy structures are also sensitive to tilt.
Methods usually considered
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Bored Piles
High loads, large diameters and rock sockets.
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CFA
Continuous Flight Auger Piles
Medium loads with fast, quiet installation.
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Micro Piles
Restricted access, underpinning and tension loads.
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Rigid Inclusions
Slabs and tanks where settlement control, not structural connection, is the aim.
Which method fits depends on the site investigation and the performance requirement. More than one may be combined.
How the choice is made
- Magnitude and type of load: compression, tension, lateral.
- Depth to the bearing stratum and groundwater.
- Access, headroom and neighbouring structures.
- Programme and verification requirements.
How the result is verified
Pile capacity is verified by static or dynamic load tests, and soundness by integrity tests.
Tests typically used
Other ground problems
Have this ground problem on your site?
Share the site investigation report and the performance requirement.