cohesion/friction for footing uplift
cohesion/friction for footing uplift
(OP)
Hi all,
For those of you who work in high wind areas (Florida here) - have you ever relied on cohesion or friction for additional uplift resistance on footings - or perhaps some other factors that will help make foundation design more economical? I have never seen or heard of footings being ripped out of the ground due to strong winds ( except maybe overturning on fences or something similar) - failure seems to start with C&C, which once destroyed, relieves the foundation of much of the uplift forces. Thanks in advance!
For those of you who work in high wind areas (Florida here) - have you ever relied on cohesion or friction for additional uplift resistance on footings - or perhaps some other factors that will help make foundation design more economical? I have never seen or heard of footings being ripped out of the ground due to strong winds ( except maybe overturning on fences or something similar) - failure seems to start with C&C, which once destroyed, relieves the foundation of much of the uplift forces. Thanks in advance!






RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
- Reduction in air density due to a cyclone/hurricane forming in a low pressure cell.
- Skin friction on piled footings. The skin friction increases with increasing soil cohesion.
- If the slab is integrated with the footings, as the slab lifts a vacuum will form under the slab, especially if the slab has an edge thickening which prevents air from accessing the gap between the slab and soil. This is the same as if you had a flat ruler under a sheet of paper and quickly tried to lift the paper like a momentary gust of wind. The longer the slab has been in place the stronger the vacuum due to air under the slab dispersing into the soil. This should be one of the larger contributing factors for residential construction.
RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
I always wondered, though, what that loud sucking sound was every time a large hurricane comes through the coastal areas.....or was that just the politicians?
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RE: cohesion/friction for footing uplift
RE: cohesion/friction for footing uplift
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