Harry Wade wrote:
At 11:40 AM 1/8/05 -0800, you wrote:
on the matter of frost heave,
I'm enraged, . . . well maybe only mildly irritated . . . . :-)
1. I am beginning to understand that what is called "frost heave", is the process whereby freezing soil at the surface of the ground can only expand UP as the water freezes.
Royce, the forces holding the post in the ground (gravity and soil friction) will be ovecome by the force of frost expansion acting upward and it will displace (jack) the post however much necessary to accomodate its expansion. That's frost heave.
Regards,
Harry
So what you're saying is that the only force forcing the post upward is from the freezing soil under the bottom of the post - that freezing surface soil expanding upward has nothing to do with it ? This would not be a phenomenon I would characterize as "jacking".
If you're right, then "hollow" posts (ie PVC tubing and galvanized pipe) don't have enough surface area (the wall thichness time circumference) for the freezing soil to act on to force the post up ?
royce in SB
