house pad moisture content question?

[beeforty]

[video]http://construction.about.com/od/Earthwork/a/Compacting-Granular-Soils.htm[/video]

Just a little more information.

I always like to flood my sand before tamping it down. As stated in above quote it settles everything down really good. I'm currently getting ready to pour a small slab on top of about 12 " of sand that I have been soaking and packing down.

 

[Billrog]

Wetting sand to compact it is very beneficial but one consideration is if your subsoil below the sand is clay over soaking may create a problem. The clay will swell and it takes a long time to dry out but when it does it shrinks causing settling. Without a site inspection or specific soil details it will be very difficult to get exacting info. That said for a bed under a trailer sand gone over with a plate tamper is more than adequate as you have very little # psf with all the blocking in place.

 

[EddieWalker]

Since this is not my line of expertise and we are just trying to help someone out that we think needs some help, I do not want to do a less than satisfactory job.
I would consider it BAD, if we did the job and it was not up to snuff. That's the reason for asking for advise, and at least learning all we can.

We have seen a Louisiana site preparation requirements that says new fill should be compacted to 95% density. Also, I find, Texas passed some new requirements for site preparation last Nov.

Just trying to cover the bases, as much as we can.

My reasoning for asking about why you need to know the moisture content is because sand is nothing like soil in site prep. You cannot compact sand like you have to compact soil. Sand is the only material that self compacts. Building on sand is simple because you don't need to compact it. It is also the weakest material to build on, so if you where building a house, you would need to take that into consideration when designing the foundation. Since this is a pad for a mobile home, I'm at a loss why moisture content is a concern?

What type of pad is this? A level place to put the mobile home on, or is this to pour concrete and create a pad to place the mobile home on?

Are you bringing in sand to build up level pad? Is the sand going over existing sand? Why are you using sand?

Eddie

 

[MacLawn]

Foolish man built his house on sand... Wise man built his house on the rock. I'd use wha' my county calls road fill.

 

[ns_in_tex]

My reasoning for asking about why you need to know the moisture content is because sand is nothing like soil in site prep. You cannot compact sand like you have to compact soil. Sand is the only material that self compacts. Building on sand is simple because you don't need to compact it. It is also the weakest material to build on, so if you where building a house, you would need to take that into consideration when designing the foundation. Since this is a pad for a mobile home, I'm at a loss why moisture content is a concern?

What type of pad is this? A level place to put the mobile home on, or is this to pour concrete and create a pad to place the mobile home on?

Are you bringing in sand to build up level pad? Is the sand going over existing sand? Why are you using sand?

Eddie

It would be a level place for a mobile home, sitting on blocks.
We are trying to make a 40'x50' pad on the side of a sand hill. It will go from no fill to 3' fill over 50' span.
Sand is moved from adjacent area by pad location. This is the only place we have found to get free dirt which we can move with our equipment.
We added another lift to it today and all seems to be looking good, EXCEPT,
on the upper end (very little fill, only removed grass) we have two small areas (6'x6') that seem to be getting weaker, the more we drive on them, as well as it seems wetter than the rest of the pad.
Maybe if we give it a day or two to dry, it will work better. Yes/No ????
We have plenty of other type dirt on my place 6 miles away, but my 56 year old dump truck is not road worthy.

 

[ns_in_tex]

Foolish man built his house on sand... Wise man built his house on the rock. I'd use wha' my county calls road fill.

And then some are never able to have a home.

 

[rustyshakelford]

Honestly, it's a bad idea to build on sand. I'm cheap and even I won't use it. Sugar sand get very loose when it drys out and I would be concerned of its stability. I'd take the unroadworthy truck over building on sand personally.

Brett

 

[EddieWalker]

If sand is all you have, then that's what you learn to work with. The load bearing ability of the sand will be fine for the mobile, but you need to make sure they put down extra blocks to spread out the load and go as deep as possible with their anchors. Probably more anchors too, but I really don't know how many.

While sand will shift on you while you go over it, it is as solid as it gets. Adding water or removing it wont really change anything with it's ability to hold more weight or compact. It is what it is. Spread it, cover it in plastic and put the mobile in place.

Eddie