Topic 'Concrete cracks -Revisited' in forum 'Home Improvement' - dslreports.com

Re: Concrete cracks -Revisited

Wed, 14 Nov 2012 02:37:13 EDT

margerydany posted : Hydraulic cement does not bond well to concrete, you can try using fast-curing resin and silica sand to fill in the wider cracks.

Re: Concrete cracks -Revisited

Wed, 14 Nov 2012 02:34:53 EDT

margerydany posted : Hydraulic cement does not bond well to concrete, you can try with fast-curing resin and silica sand to fill the wider cracks.

Re: Concrete cracks -Revisited

Wed, 07 Nov 2012 16:57:30 EDT

averagedude posted : Nicely done!

Re: Concrete cracks -Revisited

Wed, 07 Nov 2012 16:32:32 EDT

Juggernaut posted : That looks darn good there, bud! Nicely done!

Re: Concrete cracks -Revisited

Wed, 07 Nov 2012 14:45:26 EDT

AMD Phreak posted : Materials and semi-finished work.

Re: Concrete cracks -Revisited

Wed, 07 Nov 2012 14:42:32 EDT

AMD Phreak posted :

Re: Concrete cracks -Revisited

Tue, 06 Nov 2012 21:12:08 EDT

TA63 posted : I know an Irish guy that can handle that for you.

His name is Phil...
--
The talented hawk speaks French.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 23:16:51 EDT

AMD Phreak posted : Wife just said she wants to replace patio with brick, like what Goober has. :huh:

I guess this project is preparation for the drive way crack?

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 22:45:31 EDT

AMD Phreak posted : Not bad actually. The dust was no where near what I thought it would be.

Pain in the neck to undercut the gap but I actually discovered the crack runs all the way through the slab in some places.

The part up against the house back sliding door, I opened up quite a bit and under cut that as well. That was probably the most dusty part, I don't know if the concrete was the worst there than else where or what.

Seemed very powdery at that point compared to the rest.
--
"Above all, I would teach him to tell the truth. Truth-telling, I have found, is the key to responsible citizenship. The thousands of criminals I have seen in 40 years of law enforcement have had one thing in common: Every single one was a liar."
J.E.H.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 22:23:22 EDT

robbin posted : Take a few pics before you fill it. How did the diamond blade / grinder combo work (other than being dusty)?

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 22:07:12 EDT

AMD Phreak posted : Got it all cut out. Will be filling it tomorrow

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 21:05:48 EDT

valvoj posted :

said by stev32k:

I've tried repairing several cracks in concrete over the years and the only thing that lasted was silicone caulk. None of the concrete patch material lasted more than a year.

+1. I've tried various concrete patches in my driveway and none worked. The only thing that worked for me was Sikaflex

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 14:41:21 EDT

AMD Phreak posted : Grabbed a grinder that was on sale at Harbor Freight and a wheel at home d. Last night I did some research on materials and I found Quickrete has a resurfacing product with polymer in it that can be used for repair and resurface. Grabbed a bag of it at lowes.

My plan is to undercut the crack, and then rinse it out. Mix up the concrete repair as per label for a mortar mix and fill the crack then top it and brush the finish to help blend it.

I know it's not the be all end all fix as some day I'll have to replace the slab.
--
"Above all, I would teach him to tell the truth. Truth-telling, I have found, is the key to responsible citizenship. The thousands of criminals I have seen in 40 years of law enforcement have had one thing in common: Every single one was a liar."
J.E.H.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 13:09:46 EDT

averagedude posted : Once you have all the concrete filled...
Have you thought about decorative concrete coatings like the attached picture (that I borrowed from Google search images).

Even a garage epoxy style coating will cover up the repairs.

decorative coating

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:54:00 EDT

AMD Phreak posted : Thanks Robbin.

Looks like a Harbor Freight trip for a grinder is in order.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:44:32 EDT

robbin posted : That's what I would use -- diamond blade dry.

edit -- Diamond wheels last a long time, even dry. No need for an air compressor either. Cheap electric grinder works well for this.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:44:24 EDT

AMD Phreak posted : I know there are grinder wheels that are meant for dry use but I just can't see using them for any long duration. They'd have to wear faster than a wet wheel.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:35:30 EDT

eagleknight posted : Might be worth it to pick up an angle grinder. You can get a diamond blade for around $20 at Lowes or Menards. They cut like butter compared to the masonry wheels. You can run them without water.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:33:42 EDT

AMD Phreak posted : OK sounds good.

I guess the time has come to spring for an air compressor. Thanks. I'll report back later.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:31:02 EDT

leibold posted : No. The blade will wear down too fast and you are making the dust problem far worse (it is easier dealing with the mud puddles then widespread concrete dust).

When I rent a concrete saw here they measure the blade diameter and fees are based on how much the blade is worn down (a big incentive to keep the blade cooled with water).
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Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:27:58 EDT

AMD Phreak posted : Alright.

I know someone mentioned using the cutting wheel to me in another thread and how to keep the thing wet. How critical is that? Could the wheel be run dry?

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:25:57 EDT

cowboyro posted :

said by AMD Phreak:

Should I even then bother undercutting it before I fill it?

Definitely won't hurt. If you have an angle grinder with a concrete cutting wheel it shouldn't be a big issue. Just wear a dust mask and goggles...

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:23:07 EDT

AMD Phreak posted : Thanks. Figured as much.

Should I even then bother undercutting it before I fill it?

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:21:05 EDT

cowboyro posted :

said by AMD Phreak:

What caused the crack and shift?

Probably the soil shifting under the slab.

said by AMD Phreak:

Bascially what you are saying is it wouldnt matter if I undercut it and repaired with cement mixture or if I caulked in a poly sealant material. Correct?

Correct. That will only prevent water from getting into the crack for a while. Eventually the pieces will shift further. How soon would only be a guess. It could be 1 month or 3 years. That repair material will not magically add shear strength to the concrete.

said by AMD Phreak:

If that is the case then the only repair is busting all of it out and pouring a new slab?

Unfortunately yes.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 12:20:51 EDT

leibold posted : I recently repaired a crack that was worse then yours because there was a vertical gap (part of the concrete path had settled because two years earlier part the soil underneath had been washed out by a plumbing leak).
Since the higher of the two slabs was the correct height I didn't want to do the grinding down that is normally done in this situation.
In order to fill the gap and level the walkway I used a concrete bonding adhesive on the dry and dustfree surfaces to prepare them for applying the new concrete. I used a concrete mixture that seemed to have all the right attributes I was looking for: vertical application, sidewalks, quick setting, non-shrinking. As suggested in the instructions for the concrete bonding adhesive I mixed the concrete by substituting bonding adhesive for the water that was called for in the concrete instructions.

It is the first time I worked with concrete but it seems to have worked just fine. Of course, two weeks is far too early to tell how it will hold up over time.
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 11:40:24 EDT

AMD Phreak posted : So if that is the case:

What caused the crack and shift?

Bascially what you are saying is it wouldnt matter if I undercut it and repaired with cement mixture or if I caulked in a poly sealant material. Correct?

If that is the case then the only repair is busting all of it out and pouring a new slab?
--
"Above all, I would teach him to tell the truth. Truth-telling, I have found, is the key to responsible citizenship. The thousands of criminals I have seen in 40 years of law enforcement have had one thing in common: Every single one was a liar."
J.E.H.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 11:36:39 EDT

cowboyro posted : Any repair will be a surface repair only. The slab is cracked and shifting, it will crack further. It's just a matter of time.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 11:07:33 EDT

AMD Phreak posted : Had to bust portions of it out as what you can't see are parts that cracked out further. I guess you could say they came out away from the main crack and then re-joined the crack I should have taken some close ups of it. I didn't see it until I was down close working and even then it was tough to see but they were there. Pretty bad in some places which is why it got wide.

I tried to undercut the thing or at least make it straight down, without opening it up.

If I were to say angle grind it to get a good undercut, then the technique would be to patch with a polymer cement mixture?
--
"Above all, I would teach him to tell the truth. Truth-telling, I have found, is the key to responsible citizenship. The thousands of criminals I have seen in 40 years of law enforcement have had one thing in common: Every single one was a liar."
J.E.H.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 09:32:35 EDT

cdru posted :

said by alkizmo:

He can still make it into a ^. His problem is that it looks like he went at it with a hammer and chisel.

Except he took what was a 1/8" crack to at 1-2" crack in places after he undercuts it.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 09:15:12 EDT

alkizmo posted : He can still make it into a ^. His problem is that it looks like he went at it with a hammer and chisel.

He needs an angle grinder.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 08:53:54 EDT

cdru posted : You kind of shot yourself in the foot. You made the crack into a V. You wanted to make it unto a ^. As it stands now, you can fill it in, but it will only chip up eventually. By cutting it like a inverted V it prevents it from popping up with the existing concrete.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 04:53:48 EDT

stev32k posted : I've tried repairing several cracks in concrete over the years and the only thing that lasted was silicone caulk. None of the concrete patch material lasted more than a year.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 03:53:55 EDT

robbin posted : I'm not sure what you hope to accomplish by this. You are not going to keep the two pieces of slab from moving at different rates. If I were to do something, I would have run my grinder with a diamond blade down the crack and then caulked it with urethane sealant. Now that you have widened it, I don't see any choice but using a cement product. It will crack again.

I guess I would mix Sakrete with admix and also paint the surfaces with the admix before patching, but I would not expect it to hold.

Re: Concrete cracks -Revisited

Mon, 05 Nov 2012 01:57:02 EDT

Smokey posted : Maybe cut some expansion joints in the slab too, and use a good sealer to keep the water out. Should help keep the slab from cracking again.
--
Para Bellum!!

Re: Concrete cracks -Revisited

Sun, 04 Nov 2012 23:13:47 EDT

AMD Phreak posted : Close up of cleaned/modified crack.

Re: Concrete cracks -Revisited

Sun, 04 Nov 2012 23:12:04 EDT

AMD Phreak posted : After

Re: Concrete cracks -Revisited

Sun, 04 Nov 2012 23:09:12 EDT

AMD Phreak posted : Before.

Dogs helping..... :)

Concrete cracks -Revisited

Sun, 04 Nov 2012 21:03:19 EDT

AMD Phreak posted : So I am finally getting around to repairing th horizontal crack in the patio. I chiseled the crack to to open it up a bit and to clear the debris today and am ready to fill.

Touching on the last post, »Concrete Cracks

I'd like to see if anyone has any newer input on the matter. I see sakrete has a top and bond product which is a concrete mixture with polymer and also has the traditional caulk in self leveling materials. Sika as mentioned in the thread prior also makes a product.

I'd like to repair it so it is a lasting repair but also one that looks half decent.

I have a bunch of left over hydraulic cement from the foundation repair I made recently but I don't think that's a good idea for this type of repair.
--
"Above all, I would teach him to tell the truth. Truth-telling, I have found, is the key to responsible citizenship. The thousands of criminals I have seen in 40 years of law enforcement have had one thing in common: Every single one was a liar."
J.E.H.