Concrete block construction with construction adhesive

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Robert

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Oct 20, 2003, 3:27:40 AM10/20/03
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I was tearing down a concrete block wall the other day and I found that most
of it could be kicked down with my foot. Evidently the job was not done
correctly.
That got me to thinking, Can construction adhesive be used to put up a
concrete block wall?

It seems to me that it would at least be as strong as a good job and a heck
of a lot easier for a novice. If so, it would be a blessing to me. I have
some property out in the desert many miles from the road. We started a house
there about 6 years ago and the expense and logistics of getting the
materials and water out there just to pour the slab and foundation was
unbelievable since the only water there had to be taken from the atmosphere.
We finaly stopped work for another alternative to hauling masive quantities
of water.

There are no building codes there but I still want it strong.

By the way, We epoxy coated the exposed rebar before we left so it wouldn't
rust.


Steven

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Oct 20, 2003, 10:16:55 AM10/20/03
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Sure, construction adhesive can be used to put up a brick wall. The true
questions would be will the wall stay up and be structurally sound? No.


"Robert" <spamcol...@tampabay.rr.com> wrote in message
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FAMILY

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Oct 20, 2003, 4:57:14 PM10/20/03
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Robert,

If you find an adhesive to bond the blocks together and then pour it solid
you shouldn't have a problem. (If you find a product for this application
let us know)

From my understanding the block wall is just a vessel holding the concrete
in and the mortar just holds the block together until poured. The concrete
and rebar is where the strength is.

I would make sure the rebars are 2' - 4' apart horizontally and vertically.
I am not sure how high the walls are going to be but I would try to pour
every 2' - 4' vertically.

Good luck,

Dan


"Robert" <spamcol...@tampabay.rr.com> wrote in message
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The Proud Infadel

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Oct 20, 2003, 5:02:32 PM10/20/03
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I think I will; just work on getting a large volume of water and go like I
origionaly itended. I wasn't thinking when I thought about this because I
still had to pour the rebar anyhow. Thanks everybody.

"FAMILY" <12343#@ATT.NET> wrote in message
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Dale Farmer

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Oct 20, 2003, 5:37:54 PM10/20/03
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Robert wrote:

If you are looking for an inexpensive way to haul water in rural areas,
check
with the local volunteer fire departments. For the cost of fuel, driver, and a
decent donation to the new apparatus fund they will often allow use of their
water tankers and temporary holding tanks.

--Dale


Matthew S. Whiting

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Oct 20, 2003, 6:25:28 PM10/20/03
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FAMILY wrote:
> Robert,
>
> If you find an adhesive to bond the blocks together and then pour it solid
> you shouldn't have a problem. (If you find a product for this application
> let us know)
>
> From my understanding the block wall is just a vessel holding the concrete
> in and the mortar just holds the block together until poured. The concrete
> and rebar is where the strength is.

No completely correct. Bare block can make a wall that is strong enough
for many applications. There are are many 40+ year old foundations
around my locale (northeast) made from lowly 8" concrete blocks that
have no filled cores, durawall or anything else. My last house was
built this way and the only problem with it was when a tree root grew
into a wall and started to crack it.

Concrete block is very strong in compression, but relatively weak in
tension so it doesn't resist bending loads very well. However, once you
put a heavy building on top, it will resist a far bit of vertical
bending load. Adding rebar and filling some or all of the cores
certainly does add much additional strength, but if you don't need it,
then it is wasted.


> I would make sure the rebars are 2' - 4' apart horizontally and vertically.
> I am not sure how high the walls are going to be but I would try to pour
> every 2' - 4' vertically.


I've never seen rebar placed horizontally in a block wall. I suppose it
could be done, but you'd have to either notch the blocks or use very
small rebar or a very large mortar joint. I've always used a product
called DuraWall (or something close to that spelling) for horizontal
reinforcement and then rebar every 4' or so for vertical.

My last foundation was precast concrete and so far I like it the best of
all! :-)


Matt

Matthew S. Whiting

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Oct 20, 2003, 6:26:44 PM10/20/03
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Yes, and it is good to get to know, and support, the local volunteer
fire department if you live in a rural area. You may need them some day
and it is good if they know you and exactly how to reach your place
should the worst happen.


Matt

Bob Morrison

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Oct 20, 2003, 6:29:09 PM10/20/03
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In article <K_Xkb.186816$0v4.14438224@bgtnsc04-
news.ops.worldnet.att.net> FAMILY says...

> From my understanding the block wall is just a vessel holding the concrete
> in and the mortar just holds the block together until poured. The concrete
> and rebar is where the strength is.
>

Not true.

Block (CMU) walls are designed in a similar fashion to poured in place
concrete. Rebar placement is critical as is placement of grout.

Mortar (the stuff in the joints) strength is dictated by the local
building code. Mortar is used because it's less expensive than just
about any other product for the amount needed to properly join the
blocks.

If you decide to use an adhesive, let me know ahead of time so I can
take out stock in the company. <grin>

--
Bob Morrison
R.L. Morrison Engineering Co.
Structural and Civil Engineering
Poulsbo WA

Lyle B. Harwood

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Oct 20, 2003, 8:20:45 PM10/20/03
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In article <3F9460EA...@computer.org>, Matthew S. Whiting
<m.wh...@computer.org> wrote:

€ I've never seen rebar placed horizontally in a block wall. I suppose it

€ could be done, but you'd have to either notch the blocks or use very
€ small rebar or a very large mortar joint.

There is a type of block sold that has two slots cut in each end, and
one knocks the chunk of block between the slots out with a hammer,
which creates a horizontal space for the run of rebar.

Since not every course will call for a run of hor bar, it's easy to mix
up the count of the types of block when you're ordering.

--
Lyle B. Harwood, President
Phoenix Homes, Inc.
(206) 523-9500 www.phoenixhomesinc.com

FAMILY

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Oct 20, 2003, 8:56:07 PM10/20/03
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The block you are making reference to are called "bond-beam block" and
usually the knockouts are all ready knocked out. most companies do not make
bond-beam block with the knock out still in. If you want a really strong
block wall look for 50/50's usually 50% pumas and 50% concrete mix. most
blocks are 25/75, 25% concrete and 75% pumas (light in weight). on the
corners or at the ends of wall you will use a stretcher block (regular
block) and make cuts appropriately.

I hope this helps,

Dan

"Lyle B. Harwood" <ly...@invalid.phoenixhomesinc.com> wrote in message
news:bn1u4t$jrf$1...@216.39.146.232...

Ed Kliman

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Oct 21, 2003, 8:38:36 AM10/21/03
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Robert:

You can dry-stack the concrete block and then shotcrete the block
walls with a mix of Portland and sand in a 3:1 mix and get a building
that will last beyond your lifetime. Mix some nylon reinforcement
fibers in from Nycon (nycon.com) with your shotcrete mix and your
walls will still be standing in the year 2500. The shotcrete sprayer
can be had for around $200 (mortarsprayer.com) and the application
layer only needs to be 1/8" so your water usage and your capital
expenditures will be minimal. You can eliminate the need for
horizontal rebar by parging your walls in this fashion. Good
construction practices call for spacing your vertical rebar/grout
columns every 4 feet.

I am building a house in this fashion adapted from and for conditions
in the Southwest. If you'd like to do a drive-by, remove the "NOSPAM"
from the URL below. You're always welcome to e-mail with questions
about technique, vendors or materials.

http://www.NOSPAMtexasmusicforge.com/gimmeshelter.html

Best regards,

Tio Ed
El Rey de Sweat Equity
Austin, Texas

JsWalkerLazenbyJr

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Oct 20, 2003, 11:26:05 PM10/20/03
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"Robert" <spamcol...@tampabay.rr.com> wrote in message
news:M7Mkb.140611$eS5....@twister.tampabay.rr.com...
> I was tearing down a concrete block wall the other day and
I found that most
> of it could be kicked down with my foot. Evidently the job
was not done
> correctly.
> That got me to thinking, Can construction adhesive be used
to put up a
> concrete block wall?
>
> It seems to me that it would at least be as strong as a
good job and a heck
> of a lot easier for a novice.

Not necessarily so, Robert . . .

. . . as to the "lot easier" part, novice or pro.

Maintaining plumb as well as aligned stretchers can be a
real pain with a product with manufacturing tollerences
suffered by cmu, unless you have a mortar joint to make up
differences. The level lines may not be so severe a
problem, but you better believe you'll have fits trying to
keep walls and openings plumb. Don't forget, when it starts
to tilt, you can't level with the mud. And, when your block
doesn't run just right to an opening, you may have to saw
1/4" off the ends or something like that, as you can't make
it up with a head joint.

Just a word of warning. Things that look very easy are more
often a first class pain in . . .

Jim
>


Matthew S. Whiting

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Oct 21, 2003, 6:07:28 PM10/21/03
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But don't you then have to knock holes in the bond beam blocks for the
cores that you want to fill vertically? Seems rather complicated to me
when their are better ways that are perfectly acceptable structurally.

Matt

FAMILY

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Oct 21, 2003, 6:45:08 PM10/21/03
to
Matt,

No, the bond-beams are made just like the regular block (stretcher block).
They both have vertical cells and the bond-beams have a horizontal slots or
opening in them for rebar.
Here are some examples of CMU block:
http://www.mutualmaterials.com/commercial/cmu_shapes4.html

http://www.mutualmaterials.com/commercial/cmu_shapes1.html

I hope this helps,

Dan


"Matthew S. Whiting" <m.wh...@computer.org> wrote in message
news:3F95AE36...@computer.org...

Matthew S. Whiting

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Oct 21, 2003, 6:56:34 PM10/21/03
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FAMILY wrote:
> Matt,
>
> No, the bond-beams are made just like the regular block (stretcher block).
> They both have vertical cells and the bond-beams have a horizontal slots or
> opening in them for rebar.
> Here are some examples of CMU block:
> http://www.mutualmaterials.com/commercial/cmu_shapes4.html
>
> http://www.mutualmaterials.com/commercial/cmu_shapes1.html


OK, so you have to fill all of the cores of all of the blocks then to
make this work. I was thinking of just filling the vertical cores that
contained the rebar and likewise the horizontal cores that contain the
rebar, however, you'd have to have a block closed at the bottom for
that. I was thinking more of a block that would be used to create a
lintel. I can't imagine that building a block wall loaded with rebar
and then loaded with concrete would be more efficient than just using
forms and poured concrete.


Matt

Lyle B. Harwood

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Oct 21, 2003, 7:42:56 PM10/21/03
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In article <3F95AE36...@computer.org>, Matthew S. Whiting
<m.wh...@computer.org> wrote:

€ But don't you then have to knock holes in the bond beam blocks for the

€ cores that you want to fill vertically? Seems rather complicated to me
€ when their are better ways that are perfectly acceptable structurally.

No, they have vertical cores.

Lyle B. Harwood

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Oct 21, 2003, 7:45:40 PM10/21/03
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In article <3F95B9B7...@computer.org>, Matthew S. Whiting
<m.wh...@computer.org> wrote:

€ I can't imagine that building a block wall loaded with rebar

€ and then loaded with concrete would be more efficient than just using
€ forms and poured concrete.

We agree on that.

I've always recommended poured concrete, with a superior product at a
lower cost being the primary reason. So far, the only significant block
wall I got involved in was taking over and finishing up a homeowner's
project.

Mark & Shauna

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Oct 21, 2003, 8:09:01 PM10/21/03
to

I just drystacked a 15 course drystack foundation. It has 7 openings in
it. I didnt have a single problem with keeping the walls plumb nor the
openings. Of course I am surface bonding the block so a 1/16th here and
there are not a problem. They will be burried when I am done. However
the 1/16th is still there in a mortar wall it is just hidden to your
eye. Taking great care in laying your first course in motar is the key.
I had though about laying the 7th course or so in mortar as a
"correction" course if I needed it but it was no necessary. Using a
transit or good sight level makes the rest of it a sinch.

Best of all when the wall is done there are no stair step cracks, its
water tight, and far stronger than a mortar wall. I have never
understood why mortar walls are still the norm.

Mark

Bob Morrison

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Oct 21, 2003, 8:54:02 PM10/21/03
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In article <3F95B9B7...@computer.org> Matthew S. Whiting says...

> OK, so you have to fill all of the cores of all of the blocks then to
> make this work. I was thinking of just filling the vertical cores that
> contained the rebar and likewise the horizontal cores that contain the
> rebar, however, you'd have to have a block closed at the bottom for
> that.
>
Actually, I believe the masons normally have a piece of screen or
something similar (could be an old shirt for that matter) that gets
stuffed in the holes below the bond beam block that don't contain
reinforcing. It is common construction to use rebar at 32" o/c vert and
bond beams at 48" o/c. Only the cells and bond beams that have bars are
grouted and it is done usually in 4-foot lifts.

FAMILY

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Oct 22, 2003, 1:13:53 AM10/22/03
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Matt,

All you have to do is install a screen on the bottom of the bond-beam course
or pour vermiculite (or something comparable, for insulation purposes) into
the cells that you are planning on not pouring solid.

Good luck,

Dan

"Matthew S. Whiting" <m.wh...@computer.org> wrote in message

news:3F95B9B7...@computer.org...

Matthew S. Whiting

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Oct 22, 2003, 6:36:52 AM10/22/03
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Bob Morrison wrote:
> In article <3F95B9B7...@computer.org> Matthew S. Whiting says...
>
>>OK, so you have to fill all of the cores of all of the blocks then to
>>make this work. I was thinking of just filling the vertical cores that
>>contained the rebar and likewise the horizontal cores that contain the
>>rebar, however, you'd have to have a block closed at the bottom for
>>that.
>>
>
> Actually, I believe the masons normally have a piece of screen or
> something similar (could be an old shirt for that matter) that gets
> stuffed in the holes below the bond beam block that don't contain
> reinforcing. It is common construction to use rebar at 32" o/c vert and
> bond beams at 48" o/c. Only the cells and bond beams that have bars are
> grouted and it is done usually in 4-foot lifts.
>

That was my thinking also, but the blocks didn't seem to be designed for
that. Seems like they could use a closed bottom block to make life
easier for the horizontal beam fabrication. I think I'd just go with
poured concrete if I needed that much reinforcement. Around here,
unreinforced block walls cost within about 10% of poured concrete which
are only about 10% less than precast concrete. I think you'd chew up
the 10% savings really quickly with the labor and materials cost of
adding the vertical and horizontal bond beams. Maybe other areas the
cost advantage is better, but here I don't think it would be economical.
And other than needing a very intricate shape, I can't think of any
other (non-economical) reason to use block.


Matt

Ed Kliman

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Oct 22, 2003, 8:28:33 AM10/22/03
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The way to deal with keeping the courses plumb is to make regular use
of a mason's level and use shims wherever necessary. Washers do a
good job as shims, but a lot of local masons like to use pennies for
this considering the washers cost 2 or 3 cents apiece. I've tried
both and both work equally well.

I have used plenty of "contractor grade" adhesive to hold parts of my
walls together and it works okay, but that's only for temporary
reinforcement until I can get the walls shotcreted, which is where the
real structural strength is. I can't think of any adhesive product
I've tried that I would trust to hold a heavy concrete wall together
considering the penalty involved for guessing wrong. I would strongly
suggest to the original poster that he do the same.

Mark is also spot on the money about being able to cover any flaws
through the parging process with the shotcrete or surface bonding
cement. I also agree with him about not understanding why mortared
block walls are the norm when dry stacked walls are so much easier and
sturdier.

Best regards to all,

Tio Ed

Js Walker Lazenby Jr

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Oct 22, 2003, 8:53:30 AM10/22/03
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"Ed Kliman" <ekli...@yahoo.com> wrote in message
news:588a6708.03102...@posting.google.com...

I suspect one answer to your and Mark's questioning mortared
block walls being the norm over dry-stacking is you and Mark
get much better cmu quality than is the norm. Consistency
in block manufacture as to plane, square and just plain ole
dimensions is not the norm. Also, normal block masonry
laying is far more of a production and less a block-by-block
labor of love than the typical DYI effort. A concrete
masonry company is seldom concerned with comparison of
pennies and washers.

I'm happy you confirmed my advice for the OP to be concerned
with plumbing his walls, etc., by commenting on various
methods of addressing course-by-course corrections. Hate to
see him get eight feet up before he either looks or falls
down.

Jim


FAMILY

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Oct 22, 2003, 3:33:28 PM10/22/03
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Matt,

Actually they do make a lentil block that has a closed bottom. You would
save money if you were just to fill the voids with vermiculite or just leave
empty and use a regular bond-beam. The bond-beam is cheaper then the lentil
block. Second you would use allot less rebar then if you were to pour you
walls.

Typically, If your fist course is a bond beam and the rebars are stubbed up
about 2'-8"+ from the footing. Then your next bond-beam course would be
either at 2' increments for strength or at 4' increments (reg. rebar
setting).

If you have an 8' or so high wall then you would have only three horizontal
bond-beams with rebar if you went with rebar at 4'.

Have a good day,


Dan


"Matthew S. Whiting" <m.wh...@computer.org> wrote in message

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Ed Kliman

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Oct 22, 2003, 4:13:13 PM10/22/03
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"Js Walker Lazenby Jr" <aajwl...@gbronline.com> wrote in message

> you and Mark
> get much better cmu quality than is the norm.

Can't vouch for Mark, but my walls looked like they'd been drinking
heavily before I figured out my block dimensions and angles were only
approximate ;-)

> dimensions is not the norm. Also, normal block masonry
> laying is far more of a production and less a block-by-block
> labor of love than the typical DYI effort.

Oh NOW you tell me. Wonder if it's too late to go with that nice used
doublewide on the easy payment plan...?

> I'm happy you confirmed my advice for the OP to be concerned

Jim, I've never known you to give anything other than sound advice on
this list, so I'm always happy to second your suggestions.

Tio Ed

Project Mangler

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Oct 23, 2003, 10:09:36 PM10/23/03
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"FAMILY" <12343#@ATT.NET> wrote in message
news:cYAlb.10991$Ec1.9...@bgtnsc05-news.ops.worldnet.att.net...

> Matt,
>
> Actually they do make a lentil block that has a closed bottom. You
would
> save money if you were just to fill the voids with vermiculite or just
leave
> empty and use a regular bond-beam. The bond-beam is cheaper then the
lentil
> block. Second you would use allot less rebar then if you were to pour
you
> walls.

The bond beam blocks I am familiar with had the slots in the end and
center webs. When laying these blocks, you just gave the webs a tap,
breaking them off. You then would place the broken-off webs in the
bottom of the block cells to keep the poured concrete from filling the
cores below. When you encountered a vertical column of rebar, you simply
left the webs open, thus allowing the voids to fill all the way to the
bottom.

jakeba...@gmail.com

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Sep 10, 2018, 2:48:21 PM9/10/18
to
On Monday, October 20, 2003 at 1:27:40 AM UTC-6, Robert wrote:
> I was tearing down a concrete block wall the other day and I found that most
> of it could be kicked down with my foot. Evidently the job was not done
> correctly.
> That got me to thinking, Can construction adhesive be used to put up a
> concrete block wall?
>
> It seems to me that it would at least be as strong as a good job and a heck
> of a lot easier for a novice. If so, it would be a blessing to me. I have
> some property out in the desert many miles from the road. We started a house
> there about 6 years ago and the expense and logistics of getting the
> materials and water out there just to pour the slab and foundation was
> unbelievable since the only water there had to be taken from the atmosphere.
> We finaly stopped work for another alternative to hauling masive quantities
> of water.
>
> There are no building codes there but I still want it strong.
>
> By the way, We epoxy coated the exposed rebar before we left so it wouldn't
> rust.

I'm 15 years too late... I'm an engineer and for those still researching this method, yes, you can build a CMU wall with adhesive (I don't explain every term, but they're Googleable). It's typically refereed to as a "dry-stack" (in the old days of mortar-less joints), typically found in retaining wall blocks. The things you must consider are the loading of the wall. Vertical and horizontal stresses will dictate how you'll want your wall to perform. Concrete holds compression loads, while steel holds tension loads, and you'll need both to for a durable wall. I would not recommend a dry stack retaining wall that is not bonded; meaning you'll need to fill the CMU with mortar or concrete. For freestanding walls, that are only subject to shear loading, mortar is unnecessary, but the wall must be mechanically anchored and fastened to a substrate that will resist shear forces. For a CMU dry-stack retaining wall, this is my recommendation: Footing - Establish a footing below the frost line (If unfeasible, then footing must be insulated, and have a substrate that allows the wall to "float" - several inches of pea gravel, and have limited reinforcement. Note, wall will shift and crack), footing should be 3 x the width of the CMU, use at least #3 rebar horizontally spaced evenly with gaps 1 x the width of the CMU. Vertical rebar need to hook the horizontals and be space every 32 inches and at the corners. Use 6.5 Sack (4000PSI) concrete for footing and CMU fill and make sure it is trowel finished perfectly level (no mortar bed to make up evenness) with a key-way where the center of the blocks will run. Wall - Every other course should be a bond beam (per-nothched blocks that allow for rebar and concrete fill), every 20 ft should have a dead leg for support, use a premium PL construction adhesive. For $100, you can buy enough construction adhesive to do a 4 course wall that is 100 ft long with a shear strengthen much greater than mortar and will bond readily with the CMU. Note, a major benefit with mortaring joints is the mortar fills voids from the natural inconsistency of CMUs, so expect gaps. Glue the three faces that will be in contact and set the blocks as you normally would. I don't describe how to set wall plum and level... Be sure to lay 2 horizontal runs of rebar in the bond beams, let the glue cure, then fill with concrete. Apply a waterproof membrane and drainage where necessary and allow concrete to cure before back filling. I recommend #4 for horizontal, and #5 for vertical rebar. Do a quick Google on rebar placement to resist loading so the rebar is arranged correctly. I do NOT recommend pouring a footing on grade where there is frost, and do NOT recommend building a retaining wall greater than 30 inches without further engineering.

chris.l...@gmail.com

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Jan 8, 2019, 10:55:56 AM1/8/19
to
Please excuse any ignorance that may come from my reply haha
I am in the process of building a 28x48 shop with block. I have been looking at a product called Bluemax and considering using it in replace of mortar. I plan on filling each corner and every 4ft with concrete. Can I do this?

Sawon Saha

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Jul 26, 2022, 9:19:14 AM7/26/22
to

Concrete block construction is a versatile and durable way to build a variety of structures, from homes to commercial buildings. When done correctly, concrete block construction can provide a strong and lasting foundation for your structure. One of the keys to successful concrete block construction is using construction adhesive.

Construction adhesive is a strong, yet flexible, bonding agent that can be used to attach concrete blocks together(http://gg.gg/11uszj). When used correctly, construction adhesive can provide a durable bond that will hold up against the elements and the weight of the structure.

There are a few things to keep in mind when using construction adhesive for concrete block construction. First, be sure to use the correct amount of adhesive. Too much adhesive can make the blocks difficult to maneuver and can cause the adhesive to ooze out from between the blocks, making a mess. Too little adhesive will not provide a strong enough bond and can cause the blocks to shift or move over time.

Second, be sure to apply the adhesive evenly to the surface of the blocks. Uneven application can cause the adhesive to cure unevenly, which can weaken the bond.

Third, allow the adhesive to cure fully before proceeding with construction. Depending on the adhesive, this can take anywhere from a few hours to a few days. Once the adhesive is fully cured, it will be much stronger and more durable.

Following these tips will help ensure that your concrete block construction is strong and lasting. Be sure to ask your local hardware store or home improvement center for more tips and advice on concrete block construction and the use of construction adhesive.
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