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How to fix patio concrete crack and steel post issue?

Dave-1
Community Megastar

How to fix patio concrete crack and steel post issue?

Afternoon All

I have an issue with my patio and handrail.

The Steel posts that were originally concreted into to the actual concrete slab have expanded with rust and cracked the concrete slab to a point where there are wedge shape gaps of concrete missing. 

I was debating to fix the concrete and put new Stirrups in or replace the metal posts with new ones and/or recondition the old ones.

I have decided to go with replace the old ones / maybe reuse the old posts after cleaning and rust proofing.

The way I was going to do it was to clean the cracked area, drill horizontal holes into the slab and put in anchors. Then use expanding concrete to fill around and bond to these anchors and post. 

The question I have is anyone have other ideas/solutions to fix the issue?

 

01 17-03-2023.jpg

This is the expanding Concrete I am thinking of using. 

02 28-05-2023.jpg

These are the anchors I wa sthinking of screwing in half way to give the concrete something to bond to.

03 17-03-2023.jpg

Another product Iwas considering but am heading towards the expanding concrete for strength.

04 27-05-2023.jpg

First Crack/wedge 

05 27-05-2023.jpg

Second crack and wedge

06 27-05-2023.jpg

I havnt cleaned the area up yet. One question is does anyone know what that yellow powder is? I will use a cold chisel to take out loose pieces of concrete, then drill and fix anchors and then put some right angled formwork (Never done that before) to hold the concrete mix in. Is there something you put on the timber/proper formwork material to make it non stick?

07 27-05-2023.jpg

Old post before I tapped it out.

08 27-05-2023.jpg

This is the rust and yellow powder? I thought maybe a byproduct of rust? Really dont know. There is another crack in another post but that has not expanded yet.

 

Noyade
Kind of a Big Deal

Re: How to fix patio concrete crack and steel post issue?

G'day/afternoon Dave! @Dave-1 

 

How much concrete is missing from the edge?

From my end it looks like a cosmetic patch?

 

Scan1342.jpg

 

Do you weld?

I have managed to concrete bolt steel plate into position - then weld pipe or square to create a railing.

I was hoping we could steer away from the stirrup approach?

 

20230529_125446.jpg

 

And I'm not a smart man (I have the sutures to prove it) but how are those concrete screws installed?

Noyade
Kind of a Big Deal

Re: How to fix patio concrete crack and steel post issue?

@Dave-1 

 

"Is there something you put on the timber/proper formwork material to make it non stick?"

 

My father used sump oil on concrete form-work.

Dave-1
Community Megastar

Re: How to fix patio concrete crack and steel post issue?

@Noyade 

:smile: Yeah it pretty much is cosmetic except that it will be supporting a post. Your sketch nails it. Think it is about a 75mm hole.
No I dont weld, Have thought of learning but never got around to it. I do have access to a workshop at my workplace that has all the trades you could wish for :smile: I just talked to one of them and I can get replacement posts cut so no issue there. Might put some bolts T wise across the base that will be embedded in the concrete. I really dont want to use stirrups in the main patio. Will if I haveto but if I can repair the existing stuff it would be far better.

 

Dave

Dave-1
Community Megastar

Re: How to fix patio concrete crack and steel post issue?

@Noyade 

Thank you, might give that a go. Would it colour the surface of the concrete ?

 

dave

EricL
Bunnings Team Member
Bunnings Team Member

Re: How to fix patio concrete crack and steel post issue?

Hi @Dave-1 

 

It's great that you've received excellent advice from @Noyade. Just to add to the suggestions made, I recommend grinding away any leftover steel still stuck to the concrete. 

 

It might be necessary to build a bit of formwork to hold the concrete patch in place. If you do build form work, just remember to spray the inside of the timber with WD40 before you tip the concrete inside. This will act as dressing allowing you to remove the timber from the concrete face.

 

If you need further assistance, please let us know.

 

Eric

 

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Dave-1
Community Megastar

Re: How to fix patio concrete crack and steel post issue?

Thank you @EricL 

WD40 sounds like a good option. If I use normal/pine timber would I get a nice surface is my main concern (Compared to buying the smooth coated sheet for concrete formwork). I always sit there and go through the steps, end up stressing too much sometimes. Mostly it comes down to me biting the bullet and kicking my butt to get me moving.

I found out that the yellow powder is possibly sulphur. Apparently when they would put the steel posts in they coated the ends of the steel in it to help bind it to the concrete. Will be getting rid of it plus any old rust/steel before hand for sure. 

 

Will keep you posted :laugh: hahahahah and no that isnt a delibrate pun. 

 

Dave

MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: How to fix patio concrete crack and steel post issue?

Normal Pine timber will give you an acceptable result @Dave-1. I wouldn't be looking for a super smooth finish, as it likely wouldn't resemble the slightly textured surface around it.

 

Mitchell

 

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Re: How to fix patio concrete crack and steel post issue?

@MitchellMc 

Thank you. Now off to scrounge some steel bar from the workshop :smile:

 

Dave

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