What is the Diffrence between Ground Beam and Tie Beam? 6

[TarikHKJ]

Hi

Is there a difference between Ground beam and Tie Beams? or are the different names for the same thing?

 

[Ron]

They are generally different. A "ground beam" refers to a "grade beam", a beam that typically spans poor soil conditions to connect two or more other foundation elements to support a slab or walls that would otherwise not be supportable by the soil.

In masonry construction, a "tie beam" is an intermediate beam used at floor levels and roof levels to provide lateral continuity of the masonry and to "tie" the tie columns or end walls to prevent lateral movement. In wood or other framing systems a "tie beam" (also called a collar beam or collar tie) is a beam section that prevents two structural members from spreading apart, such as roof rafters.

 

[hokie66]

Agree with Ron about the ground beam or grade beam. It is a beam which carries vertical and possibly horizontal loading between support points, and just happens to be at the ground level. A tie beam can be in the ground as well, but its purpose would be primarily to carry axial loading, mostly tension.

 

[TarikHKJ]

Thanks Ron and hokie66, very clear and helpful information.

Much appreciated!

 

[KootK]

There's plenty of variation in the use of the two terms but, in my regions of practice:

Grade beam: soil level beam transferring loads delivered by superstructure above, or expanding soil below, to discrete foundation elements (piles/footings).

Tie beam: soil level beam connecting two or more vertical load carrying elements -- usually columns -- for the purpose of stabilizing those elements laterally, particularly in the context of high seismic motion.

Often, you'll have grade beams around the perimeter of a building supporting the exterior walls and tie beams in the interior stabilizing isolated column foundations. When tie beams are required in the interior of a building, usually the perimeter grade beams will also serve as tie beams. And, of course, you sometimes have grade beams in the interior of a building as well to support interior bearing and shear walls etc.

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.

 

[Ron]

KootK....funny how terminology is sometimes regional! Here in Florida, we rarely use grade beams and almost never is one considered a "tie beam"; however, in other areas that is consistent terminology. Here, a "tie beam" is almost exclusively related to masonry construction and the tie beam is always above grade, usually at some intermediate point.....either a tall masonry wall or at masonry floor lines/roof lines.

 

[KootK]

Well, we use the tie-beam term for masonry in my neck of the woods as well. I tailored my response above to my expectation that the OP is comparing two elements of at grade, concrete construction. We'll have to let her let us know if that is accurate.

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.

 

[hokie66]

Yes, terminology varies widely with geography. While I understand your use of "tie beam" in masonry, frankly I can't remember the term used in that way. Is it the same as a "bond beam"?

 

[jimstructures]

In the USA Midwest pre-engineered metal building industry a tie beam is a reinforced concrete beam "tied to one column, extending across the width to the building and tied to a second column at the foundation elevation taking the kickout or horizontal column reaction load, instead of hairpins or a large foundation block or pad.

They described in the Butler Manufacturing Company Foundation Design Guide, 1985 Edition.

Jim

 

[KootK]

I was reviewing plans from the 60's last month for a school reno. There, tie beams were concrete beams poured at the top of load bearing masonry walls, integrally with the adjacent floor slabs. They were quite handy for my purposes really. New hallway doors work great under 16" concrete beams.

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.

 

[Ron]

Hokie66....yes...tie beam and bond beam are the same.

 

[TarikHKJ]

@KootK you are correct, I am talking about tie/grade beams in reinforced concrete construction at grade.

Thanks for the tailor made explanation

small followup: can tie beams not be at grade?

 

[KootK]

You're most welcome TarikHKJ.

Tie beams can definitely be at grade. Most are I think. I only wrote "at soil" level so as not to preclude the case where your tie beams are a story or more below grade in a structure that includes a basement. Most folks consider grade level to essentially equal main floor or the level of the ground outside of the building footprint. Perhaps "foundation level grade beam" would have been better terminology.

In terms of construction, I often see tie beams of this sort constructed as merely slab on grade thickenings.

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.

 

[BSVBD]

TarikHKJ,

Although these terms could represent many differing applications, since you are...

...talking about tie/grade beams in reinforced concrete construction at grade.

I would refer to jimstructures comments as most applicable.

The "ground beam" would likely refer to a grade beam foundation or perimeter beam where, for economical purposes, this foundation system could be chosen where a 4' or frost wall is not preferred. (Believe it or not, we design many grade beam foundations for commercial buildings in Wisconsin.)

The tie beam may likely be referring to the tie-rod(s) encased in concrete. The steel tie-rods would be mechanically connected to the bases of opposing metal building columns possessing a considerably higher horizontal thrust that is too high for the typical hairpin to resist.

In addition, I agree with Koot:

you sometimes have grade beams in the interior of a building as well to support interior bearing and shear walls etc.

Outside of the OP quote above, i cannot deny the other references to the terms.