aside from preloading soil, what other methods to minimize possilble foundation settlement?
aside from preloading soil, what other methods to minimize possilble foundation settlement?
(OP)
If I'm trying to minimize possible future settlement for my foundation. I will put 6" compacted subgrade below the foundation. Other than that what else can be done. I was told to preload the soil with 5 to 10 feet of soil then remove it before putting the foundation. How much time are we looking at this if we want to do this approach? What other method can we use? Any Geotech here want to take a shot?






RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
Then, what is the stuff below? Soft highly plastic clay? loose sand? Old landfill? How thick?
Length of time for pre-loading can vary. In most cases I am familiar with, such as peat, I shoot for one month. I have had surcharges siting for a year, but then it didn't take as high a pile.
Another technique, such as uncompacted fill, removing only part and replacing with compacted fill works.
6" of compacted gravel below a foundation would only serve to stabilize so you can work there. Not effective for reducing footing size.
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
As for other options, you could always use a deep foundation to rock. That pretty much minimizes the settlement potential.
As for the suggestion to oversize the footing, might work; but it depends on the soils. I've seen cases where making the footing larger actually increases the settlement.
Mike Lambert
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
www.PeirceEngineering.com
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
http://www.eng-tips.com/viewthread.cfm?qid=404935
That would be a question for the geotech. In addition to preloading, I have seen soil reports that recommended vibratory compaction, but that'd be questions for the geotech as well.
With the circumstances described in that previous thread, my initial thought is to design for that very low bearing, make the slab high enough above grade to allow for large settlement, design it so it can be supported in the center only or two edges only without failure so it won't much matter how it moves around. It wouldn't be cheap, but still likely cheaper, quicker, and simpler than the alternatives. I haven't tried running any numbers to see how practical, though.
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
wood piles are fairly cheap
When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.
-R. Buckminster Fuller
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?
www.PeirceEngineering.com
RE: aside from preloading soil, what other methods to minimize possilble foundation settlement?