Strip footing is too shallow..how to deal with frost heave?
Strip footing is too shallow..how to deal with frost heave?
(OP)
We have recently designed a low-rise building with perimeter strip footings. These strip footings were placed at 1.5 meters (5') below the top of slab, as recommended by the geotechnical report to prevent frost heaving. There is an issue where on one side of the building, the top of grade is actually 600mm (2') lower than the remaining sides, leaving the foundation wall exposed on that side only. This is an oversight from the design stage. Loosing the 600mm (2') soil cover means that I do not meet that 1.5 meter requirement specified by the geotechnical engineer for frost protection. It is a rather small masonry building (30' x 60'), but the exposed foundation is on the longer, load bearing side. To complicate matters, the property line is only 3' from the exposed foundation.
Any ideas folks as to how I can remedy this situation? Thank you so much in advance!
Any ideas folks as to how I can remedy this situation? Thank you so much in advance!
Clansman
If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.






RE: Strip footing is too shallow..how to deal with frost heave?
RE: Strip footing is too shallow..how to deal with frost heave?
RE: Strip footing is too shallow..how to deal with frost heave?
thread507-278313: Insulation required for frost protected shallow foundation
thread256-273: footing insulation
thread592-169967: Design Concrete Slab on Grade
thread507-197635: Turndown Footing Technique, No Frost Depth worries!!
See "Design Guide For Frost-Protected Shallow Foundations" (free .pdf download) at this link
http://
ASCE publishes "Design and Construction of Frost-Protected Shallow Foundations" (SEI/ASCE 32-01)
RE: Strip footing is too shallow..how to deal with frost heave?
RE: Strip footing is too shallow..how to deal with frost heave?
This is a footing that is already poured, the structure is constructed. It is very difficult to have the contractor excavate down to the footing and place the insulation, especially given the space constraint. Although this may be my only option.
I am curious as to how chemical grout injection works. I wasn't able to find any material on this subject online.
The soil around and beneath the footing is silty clay and highly plastic. Sounds like very frost susceptible soils to me.
Clansman
If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.
RE: Strip footing is too shallow..how to deal with frost heave?
Mike McCann
MMC Engineering
RE: Strip footing is too shallow..how to deal with frost heave?
Yes I can, but this would only add soil cover less than 1 meter away from the face of the foundation wall (the property fence is 1 meter away), would this be enough? I would think you would need at least 2 meters laterally soil cover.
Clansman
If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.
RE: Strip footing is too shallow..how to deal with frost heave?
Mike McCann
MMC Engineering
RE: Strip footing is too shallow..how to deal with frost heave?
Clansman
If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.
RE: Strip footing is too shallow..how to deal with frost heave?
Next option - could you get an easement to extend the rockery beyond the property line by two feet or so?
Mike McCann
MMC Engineering