Fixing my concrete wall

[samuttodd]

I thought I'd run this past our folks that do their own around the home repairs to get an idea of the best way to tackle this.

 

I have a concrete wall back around our patio.  The back patio is built over a swamp that is tidally influenced on the edge

of the river.

 

A portion of the wall has been compromised.

 

Here are the photos.

 

From the inside (you can see daylight through the crack)  The support posts on both sides seem sincere,

but I believe the post on the left has settled vertically and dropped sightly lower than the post

on the right.   Causing the crack to form where the wall was weakest.

 

 

Here is the foundation... It appears good,  no cracks that I can see..

 

In the lower section you can see that the whole thing is built over a swamp.   I

can not access the swamp side of the wall. 

 

 

The whole wall was built from the interior of the patio from the bottom up.

 

 

Here is the wall from the back.

 

The  blocks on the back side of the wall have cracked diagonally through

and through,  rather than along the contrete in between them (where I'd think they'd want to crack.)

 

 

So how would you deal with this?

 

I am thinking that until the top part of the wall completely fails and falls into the swamp,

any fix will have to be simply cosmetic.

 

If and when it does fail,  I can rebuild the fallen portion from the bottom up on the inside of the

wall bondaries.

 

 

What would be the best treatment to keep the crack that has formed from getting worse in the meantime?

 

 

 

Edited February 13, 2020 by samuttodd

[frequentatore]

These walls continue to move over the years. I fixed with concrete a large crack (10 cm) between two shophouses and I had to fix it again 1 or 2 years later.  

It's a small crack, use some wall putty and repeat when necessary. On the swamp side. I would attach a ladder to the top of the wall and fix it with concrete.

 

[Kwasaki]

33 minutes ago, samuttodd said:

So how would you deal with this?

 

I am thinking that until the top part of the wall completely fails and falls into the swamp,

any fix will have to be simply cosmetic.

 

If and when it does fail,  I can rebuild the fallen portion from the bottom up on the inside of the

wall boundaries.

 

What would be the best treatment to keep the crack that has formed from getting worse in the meantime?

Personally if it's something you can see all the time from the house it would annoy the likes of me and I would renew the subsided section.

My wife would probably say don't look at it. ????

 

Many type of suitable products available for temporary re-rendering the affected section of wall.

[Farangwithaplan]

Planters on the slab with passion fruit vines growing from them to cover the wall. Until that left column decides to settle, you will continue to get cracking.

 

The top rail in the photos near the left column shows noticeable deflection deforming it.

 

As others have said, you could keep filling the crack and that will help keep moisture out and help stop any embedded steel from rusting and causing more issue.

 

[worgeordie]

As long as the wall is not tilting backwards towards the swamp,

I would not worry too much, you can never really fill those cracks

in, they just open up again.

regards Worgeordie

[samuttodd]

It doesn't appear to be tilting fwd or back..   So,  that is one positive.

 

[Morakot]

Quote

any fix will have to be simply cosmetic.

 

Yes! This is not hairline crack, but a substantial damage that cannot be patched up.

 

The good news is that doesn't seem to be a structural issue with the re-enforced concrete; it's merely the masonry part. The cause by the looks of it, are inadequate size of joints and one-sided rendering.

 

A proper fix would be to rebuild parts of that section.

Edited February 13, 2020 by Morakot

[bankruatsteve]

Are all those splotches an attempt to paint?  Maybe paint a mountain scene with the crack being the slope of the mountain.  Until you might see some serious movement, I wouldn't worry about it.

[samuttodd]

33 minutes ago, bankruatsteve said:

Are all those splotches an attempt to paint?  Maybe paint a mountain scene with the crack being the slope of the mountain.  Until you might see some serious movement, I wouldn't worry about it.

no,  My S.I.L. tried to patch it with some cement.  tHE WALL HAS BEEN UP THERE FOR ABOUT 4 YEARS,  THAT IS THE ONLY SPOT THAT HAS GIVEN US TROuble, 

 

I'm going to wait until the top topples and then I'll rebuild that section.

[thailand49]

First, did you buy your home in a project? From one of the photos it seems long just for one home?  If so, it would be the responsibility of the project just as you were living in a Condo.

 

My brother lived in such a project the retaining wall was built over a swamp or stream.  If you seen how it is done no engineering seem to be in their thoughts when doing so.

 

Slowly do to the swamp the pillars are being undermined or slowly sinking whatever you do the cracks will return you can see the pillar on the left bottom with mold either when it rains heavy the water level is coming up enough to create the mold or you have standing water area in this area too.

 

You wall kind of looks even like what my brother?  Prior to the section completely falling here is what I did, I took a screw driver and open up the crack and injected foam insulation when dry I cut the excess and sand, I also from your photo noticed mold at the top of the wall along the top ledge seal all the cracks so when it rains the water don't leak from the top also seal the bottom I noticed cracks too. Take a mixture of water and bleach and clean off the wall and area to rid the mold, got some primer for old cement, two coats and then repainted the wall with desire color semi gloss.

 

The job I did for him lasted another 8 years when the wall finally fell in a big storm, meantime I told him find a good engineer not a local migrant worker when you need to replace. Meantime he notified his project of the problem when it fell it took another year because of the cost and fighting. When it was done it wasn't cheap they pile drove the concrete deep into the stream.

 

Good luck you will need it!

 

 

[Dundee2308]

You could ask Mr. Trump. He is the specialist in walls. 5555

[Muhendis]

On 2/13/2020 at 2:57 PM, bankruatsteve said:

Are all those splotches an attempt to paint?  Maybe paint a mountain scene with the crack being the slope of the mountain.  Until you might see some serious movement, I wouldn't worry about it.

Nice idea. Are you related to Banksy?

[Macthehat]

Looks like the bamboo founds have dropped . Take your wife's advise until they've settled ,then assess .  

If structurally sound then plaster the wall with sand and cement remembering to prime the wall before hand .

[lanng khao]

I'm a artist in burnt clay(bricky) id just build another skin of blockwork Infront of it, should last for a while, probably see

you out...

[eyecatcher]

Its not clear from the photo what the foundation is.

You say its solid, but all i can see is a row of damaged corrugated roof panels pushed to the underside of a foundation.

Was that the original shuttering that was supposed to be insitu and since got wet and perishing away?

 

The crack in the wall is structural. You have rotational movement on that foundation causing a diagonal crack that didnt chose the easy route via the joints which is normally the route expansion cracks go.

For cracks to split bricks and blocks its serious.

You can see the deflection in the top plinth, put a spirit level on each side to see whether the left or right side has dropped or heaved.

Remember a flooded clay soil will expand causing a heaving effect, the opposite to settlement.

 

On the back side, follow that crack right down it will lead to the crack in the foundation but due to rotation you may not even be able to see it without a magnifying glass.

 

Still interested to know what exactly is holding up the wall foundation.

Edited February 15, 2020 by eyecatcher

[sirineou]

since it is a diagonal crack rather than a vertical one, it indicates one corner of the wall has settled at a different rate than the other, this is normal for long lengths of  perimeter walls  . Notice that the crack at the bottom is narrower that the top which is wider.

Such a crack is better than a vertical crack which would indicate total separation. 

  Monitor the top of the crack to see if it gets wider, if it does not , it means that the settlement has stopped and stabilised. and the crack can be filled with mortar. if it still getting bigger  then the settlement has not stabilised yet  and if you filled with mortar it will open up again.  if it has not stop settling and you want to close the crack, you should  fill it with a flexible  type of filler such as caulking to prevent water infiltration.

 If the wall was build correctly, there should be a thin rebar or web rebar running horizontally every few courses of block..

This being Thailand, most likely small pieces of rebar (picture from my wall) a longer piece is and should be installed but this is the only picture I could find.  

This will keep the wall from falling inward or outward, but allow long lengths  to settle at different rates as it is normal . you can't expect 10m of  perimeter wall to settle at the same rate. 

but it is important to seal the crack to prevent the rebar from rusting. 

I tried to keep the explanation simple, I hope I explained more than I confused. 

 

 

 

[mogandave]

Were it me, I would chisel as much of the patching off as possible, scrape out the crack and fill it with acrylic sealant, clean the excess off with a wet rag. Let it dry for a few days and top it off where it shrinks. 
 

 

[Tropposurfer]

Remove it completely (its very unlikely you'll ever be able to build any block, brick structure on that foundation that won't crack). Your issues in subsidence/settling into the swamp.

If, if the foundation had been built to remain in one piece (float so to speak) there would be far less possibility of cracking.

I'd suggest a completely different tack;

Put up a flexible barrier. I'd suggest either a Colourbond lightweight steel sheeting fence available in a huge range of colours (Aussie product available here) or a well designed timber fencing.

NOTE: You'd have to treat the timber very well and redo the coatings every few years to keep it free of termites, wood worm, n rot. If you could source teak at a reasonable price that would be ideal.

A flexible structure will allow for movement and you won't see it (well ... it may look out of level eventually as the picture you posted shows but this can be disguised too by growing a green wall or placing some attractive planters along the wall and growing a narrow upright plant in them so you don't loose the space on the slab along the wall (there are lots that will do the job).

What about getting a Thai bamboo specialist dude to build you a bamboo structure and use a sealer on it so the colour is enhanced (bamboo preserved for a lot longer too!). 

Mount it to steel posts and steel frame set into feet bolted into the concrete slab. strong as and the natural covering material is much softer on the eyes and pleasing (you can get tonnes of great Japanese bamboo fencing ideas on the internet as a template for the guy who makes your fence).

If your an anal kinda guy or simply like engineering stuff you could actually build it so as the foundations move you could adjust the posts and therefore the level of the structure.

You could design windows into the structure too for added appeal so that the greenery beyond can be seen

The cost to attempt (yes it would be no less than a futile attempt I think) to redo foundations which is what might be an ultimate solution would be a big deal and probably overkill.

If the slab leading to the wall was in danger of breaking apart then that option might have to be considered. 

How far away is the house and other structures? Are there any issue with house walls or floor cracking?

To ensure no subsidence in a swamp area is almost impossible, you'd have to drive piles down a long long way and even that in certain swampy areas wouldn't work as there may be no bedrock to reach down for. The cost too would be a hell of a lot of baht anyway and more than likely fail. (I was a pretty competent builder, with considerable structural experience in NSW for a long time so I have some cred in what I'm saying.)

[memooz]

Dear Samuttod friend

If you need a serious help; here is sketch drawing for you, for the future , when you need rebuild this wall again.

I am 70 Yrs old Licensed builder from Aus. and study Architecture, and love these walls. They plant walls like planting a flower to your garden, then wall goes all over the place, you are lucky it is not retaining any load behind it. You can not make these walls from those concrete blocks which they are like crackers. You need a formwork and steel work and good concrete, NOT a watery Thai concrete. If you need to ask more I am here to hep friends, can contact me via email [email protected]   regards

 

[memooz]

I think TROPPOSURFER is very much correct about his comments.

[Morakot]

On 2/15/2020 at 4:31 PM, eyecatcher said:

The crack in the wall is structural. You have rotational movement on that foundation causing a diagonal crack that didnt chose the easy route via the joints which is normally the route expansion cracks go.

 

Really? @eyecatcher do you think there is differential settlement? But the crack is in the middle of the wall and not at the end. If there is movement, the parts of the wall next to the cracked section would be show damage too. @samuttodd is there damage elsewhere?

 

 

On 2/15/2020 at 4:31 PM, eyecatcher said:

Still interested to know what exactly is holding up the wall foundation.

 

Should this be the usual concrete pylons? Aren't the corrugated roof panels merely used to keep the filling in place to prevent it drifting into the swamp?

[eyecatcher]

27 minutes ago, Morakot said:

 

Really? @eyecatcher do you think there is differential settlement? But the crack is in the middle of the wall and not at the end. If there is movement, the parts of the wall next to the cracked section would be show damage too. @samuttodd is there damage elsewhere?

 

 

 

Should this be the usual concrete pylons? Aren't the corrugated roof panels merely used to keep the filling in place to prevent it drifting into the swamp?

Its not clear whether its settlement or ground heave, thats why you need to check the verticals and horizontals of each side of tge wall. That will quickly establish the real story.

If its all built on randomly spaced piers without sufficient bearing area then my best guess based on only the photos would be that the columns supporting the wall running to the left direction(of first photo) have settled abd breaking its back at the steonger pier at the crack area or the stronger pier has heaved in the saturated clay subsoil

[samuttodd]

THE concrete wall  straddles what used to be the area alongside the lower river,    but when they built the seawall,  at the riverside,  it made the section underneath a shallow swamp area (less than 1 m deep at high tide)  

[rumak]

On 2/13/2020 at 3:31 PM, samuttodd said:

no,  My S.I.L. tried to patch it with some cement.  tHE WALL HAS BEEN UP THERE FOR ABOUT 4 YEARS,  THAT IS THE ONLY SPOT THAT HAS GIVEN US TROuble, 

 

I'm going to wait until the top topples and then I'll rebuild that section.

If you can "live with it".....   as i could,  then the suggestions from others to just wait it out are what i agree with.   I would probably mix some concrete and paste it over the larger cracks (pushing it in much like spackling).(do it on both sides)   Sure, it won't solve the problem but certainly might prolong the time before it tumbles down.     Also,  good idea about planting some vines or something on inside or get creative.   

Edit:  just read some of the more instructional comments on how to build a proper wall.   I am pretty sure they are correct.  My comment is based on what I would do......  but I am probably more frugal and a bit more prone to live with some imperfections .    When it comes to what i expect from a friend or lover,  now there is where I become very particular .      

Edited February 17, 2020 by rumak

[bankruatsteve]

On 2/15/2020 at 10:59 AM, Muhendis said:

Nice idea. Are you related to Banksy?

Nah.  But, I have a artist daughter who started by doing murals.  It's a great art form and can make <deleted> look cheerful at least.  ????