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TerraFirma Excavating
03-16-2005, 05:37 PM
I read an article a few years ago in Fine Homebuilding of a home built pre-cast stone masonry walls. Here's a link to the article and pictures Stone Home (http://www.hollowtop.com/cls_html/tiltup.htm).

Although, I wouldn't build my home like this, I thought it may be a great way to build nice looking retaining walls. The walls could be poured when work was slow and stored until needed. Any hardware to lift or anchor the walls could be precast. A cap rock could then be applied with motar after install. Walls could be made in a standard size (either 4' H x 10' W or 3' H x 10' W) and moved with a loader or forklift. I think this could greatly reduce labor cost, yet still end up with a great looking end product.

Does this sound feasible?

cgland
03-17-2005, 01:08 AM
How would you install the goegrid on a taller wall? ;)

TerraFirma Excavating
03-17-2005, 01:48 AM
I figured using ground anchors or polymer reinforcement attached to points on the back of the panel (must also be attached to reinforcement embedded in the wall). This would be similar to pre-cast panels utilized in highway overpasses and clover leafs.

The more I think about this, the more I think there will be more money in labor and materials than if I utilized pre-cast blocks. I would still like to hear any more comments or suggestions from others, both negative and positive. Thanks.

cgland
03-17-2005, 10:11 AM
You can't really make a comparison to sound barriers and retaining walls. They may look the same, but there is absolutely no load being placed on a sound barrier. A retaining wall has to deal with alot of earth pushing on it not to mention hydrostatic pressure. I just don't think you can properly install something like that as a retaining wall. Looks nice though.

Chris

TerraFirma Excavating
03-17-2005, 12:05 PM
I am talking about retaining walls which hold back the backfill material of the roadway against a lower level of an on ramp at a clover leaf. I have seen 20' to 25' tall retaining walls at intersections which are in hilly areas. Most of the concrete panels just have wash aggregate finish, no stones laid in the panel. Obviously the panel will have to have reinforcement because the concrete will need to hold back tremendous pressures.

MarcusLndscp
03-17-2005, 12:36 PM
We were working on a job last year in a new development on the side of a mountain. The main road winds up through the side of the hillside like a big S. The area between the sections of the road were quite steep and they really could not do much with these areas as far as erosion control....no walls, seeding would never hold up....it was just too steep. I'm not going to get the full process correct but they opted to spray concrete directly onto the soil surface kind of like you would a pool. To the best of my knowledge a rebar cage was not put up first but I don't know why you wouldn't. I do know that large anchors were driven into the bank horizantally all along the area and had large discs that were left sticking out kind of like the head of a nail. The concrete was then sprayed over the banks to lock everything together. Did that make sense? The concrete was dyed to look like the existing ledge that was below this area and after it was sprayed they had guys up there hand shaping the concrete and putting grooves in it to make it appear like the real ledge. For what it is it really looks nice and would never have thought it to be fake. I couldn't believe it when I was told what it was. The only drainage that exists behind these are LARGE surface swales. This is their first winter and the amount of water that comes off these hillsides in the spring is unbelievable. I will be curious to see how they react to it.
Have you guys heard of this method?
Mark

jreiff
03-17-2005, 10:08 PM
Sounds pretty interesting and like it would be alot of hard work on a steep slope.

You have any pictures of it. Would be nice to see how it turned out and looks.

MarcusLndscp
03-17-2005, 10:50 PM
Unfortunately it's buried under quite a few feet of snow right now but when spring comes I will try to get a pic. I wish I had been there to watch them do it because I was amazed at the end result.
Still curious whether or not anyone else has seen anything like this done before.

D Felix
03-20-2005, 10:34 AM
They probably used gunnite, which is (I think) a drier form of concrete. It's usually "shot" with some sort of sprayer. I've never seen it done, just know the process.

Most pools that have gunnite have a wire mesh imbedded in them, maybe that's what was used for re-inforcement?

As for the pre-cast panels, there is a major drawback to them: you can really only go in a straight line. Which would be fine for large commercial-type work, but for residential it wouldn't look good.


Dan

MarcusLndscp
03-20-2005, 11:18 AM
Yes Dan, same type process as gunite. From what I'm told there was no rebar in it but I can't imagine doing it without any. It was all blown on in the same manner as gunite would be. It just amazes me that it's able to hold up under the amount of hydrostatic pressure it receives. There are ski slopes all around the area so in addition to natural snowfall they are constantly making sno as well. You wouldn't believe the volume of water that comes off the mountain come spring time. Always makes for an excellent mud season