Linkseal question 2

[looksatstars]

I have not used this linkseal system before but it seems on site the concrete slab is 16" think but the linkseal is only 12". Isn't the seal supposed to protrude for both top and bottom? This is for a hdpe water pipe coming into a small treatment plant.
Thanks

 

[JedClampett]

I'm not sure exactly what you mean by the Linkseal being 12 inches, but it doesn't have to project out of the opening.

 

[looksatstars]

Sorry, They have been calling it a linkseal but I guess what im really talking about is the steel collar that is on the outside of the linkseal.
My thinking is that the collar penetrates thru the concrete slab so if the slab heaves the pipe inside wont be stretched with the slab.

 

[JedClampett]

I'm still confused, but I'll try to answer anyhow. Linkseal shouldn't restrain pipe if the concrete heaves (by the way, if your concrete moves that much, you have bigger problems), it's to prevent water penetration, not pipe support. I don't know why the pipe sleeve needs to be longer than the slab is thick, but if they're really using a 12 inch sleeve in a 16 inch thick slab, they're wasting the use of a sleeve at all. The sleeve provides a better surface to seal against than a concrete surface and it provides a form to pour against.

 

[SteveWag]

Thunderline "LinkSeals" will work with cast-in-place holes, cored holes, or plastic/steel cast-in-place sleeves. Normally I use cast in place steel or stainless steel sleeves with a welded water stop, with the ends flush with the wall surface. Most form guys dont like to put holes in their forms, and my structural guy dosen't like large cores. I normally put some kind of flexible joint as close as possible on the exterior when worried about earth movement. I normally use two seals with both placed so the bolts can be tightened from inside. Choose your hole size fron the charts on Thunderlines site.

Steve Wagner

 

[4everlearning]

Yes, use sleeves. We've had issues with out-of-round holes in concrete pours and trying to seal with Linkseal. Although, Linkseal is typically installed w/out the sleeve. Savings that you thought you would get by not installing the sleeve vaporizes when your paying someone to chip out the out-of-round hole, repair with grout, and finally install the Linkseal.
I would install the sleeve extended 4" above the floor (2" if wall pen). Installing slleeve gets you two things ... 1. separates movement between slab and pipe (as opposed to pouring concrete right up against the pipe), and 2. helps protect the pipe from such things as rolling stock.