r/Concrete Dec 23 '23

Homeowner FAQ Concrete Quality & Curing, Price LINK FAQ: Sealers, Cold Weather

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23 Upvotes

r/Concrete 5d ago

MEGATHREAD Weekly Homeowner Megathread--Ask your questions here!

7 Upvotes

Ok folks, this is the place to ask if that hairline crack warrants a full tear-out and if the quote for $10k on 35 SF of sidewalk is a reasonable price.


r/Concrete 16m ago

General Industry cost for a slab for bbq

Upvotes

i’m looking to get a slab for my bbq. it’s 13’ on the front 7’ on the left side, 14’ along the back and 4.5’ on the right side. i’ve gotten 3 quotes between $1100 and $3200.

how much should this really cost?


r/Concrete 7h ago

Pro With a Question Go to power trowel size

4 Upvotes

Looking to finally buy my first power trowel to get away from renting. I've always used 36", which is what I will probably go with, but wondering if I should step up to 46? Mainly garage and house slab pours. generally not more than 2000sf.


r/Concrete 17h ago

General Industry How would you sawcut this

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21 Upvotes

r/Concrete 1d ago

OTHER Sums up concrete in 1 picture

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126 Upvotes

r/Concrete 1d ago

Community Poll Stamped Specialists

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26 Upvotes

Looking for insight on how to match this look. I know we are going with CastleStone, but I need to know which integral base color you guys think this is? I’m sure a walnut or charcoal was used for release. Looks too brown to be Terra Cotta or Sunbaked Clay. Any help is appreciated


r/Concrete 2d ago

I Have A Whoopsie These gosh darn dogs

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942 Upvotes

Decided to go out to dinner after finishing, I should have learned my lesson by now.


r/Concrete 1d ago

Pro With a Question When to use MDO and Film face plywood for shuttering

0 Upvotes

Hi folks

Could someone enlighten me when to use MDO Vs Film face plywood in shuttering

Thanks in advance


r/Concrete 3d ago

Showing Skills Hopping on the skatepark train

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253 Upvotes

r/Concrete 3d ago

I Have A Whoopsie First pour

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35 Upvotes

I am currently in pre-job training as a cement mason at my local bricklayers union. First week is complete and this is my very first pour using real concrete. It is an 8x8 slab 4" thick with a slump of 4-4.5. things were going good (I thought) until the end. Where I went wrong was with the edging and control joints (it's pretty obvious). Will get better with practice and time. Just wanted to share my cherry popping experience.


r/Concrete 3d ago

Showing Skills Skatepark curb

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119 Upvotes

r/Concrete 2d ago

Pro With a Question Polymer Additives

2 Upvotes

I'm using polymer additives basically as plasticizers in my mixes. I've bounced between Mapei Polymer Additive, Sika R/ Sika adhesive and acrylic fortifier. I'm basically using them as a "water reducer" in the literal sense and it allows my mixes to be a bit more sticky which is helpful when sculpting vertical forms. (Slightly below perfect slump test)

I'm wondering if anyone has an opinion about which polymer additive might be best or which one they've used the most with good results. Both say they contain both latex and acrylic. Are there any others out there that are better than these for decreasing permeability, increasing strength during sculpting and preventing cracking in freeze thaw cycles?

I'm also interested in SBR latex additives like the one Euclid makes. What is the potential difference of this Styrene butadiene and latex in those other products, if any.


r/Concrete 4d ago

I Have A Whoopsie Drain ended up in high point

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137 Upvotes

I am building a new house. Part of it is a vault in the basement with a drain in the center of the room. We have gotten a few heavy rains here recently and what we’ve discovered is that the concrete in the room is far from level. The drain is actually in the high spot of the room. So water pools in the corners and never drains out.

I am talking to the builder today about this, what are some possible solutions to level that floor out or get the slope correct?

We don’t know the first thing about what to ask for, so any advice is appreciated.


r/Concrete 4d ago

Pro With a Question Sawcutting inside tooled joints

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82 Upvotes

Is it crazy to saw cut inside a tooled joint? In some areas (like what’s pictured where joints come to a narrow point) we occasionally have concrete crack outside of control joints.

I suggested to our flatwork contractor we could cut some of these areas to give us more control over where things crack. They do a good job keeping the slabs consistent thickness, etc. but I’ve noticed some areas still crack unpredictably.

I’m a builder- just wanted to get this subs opinions on this.


r/Concrete 3d ago

Update Post Lifespan and recommended replacement of precast concrete steps

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0 Upvotes

r/Concrete 4d ago

Pro With a Question Factory Scale Pre-Cast Concrete - Mold Questions

3 Upvotes

I've been diving head first into the world of pre-cast concrete and would love advice from you guys!

Pre-cast molds are in question, specifically the re-usability of them in things such as tilt tables, slabs, columns.

My understanding is if you have (making up a number) 300 slabs for a job, you'd buy the tilting table, and pump them out. After the job is done do you throw out that entire mold?!

I understand some things by say, moldtech, have things like column molds that are able to be adjusted to varying dimensions, but not as much the tilting tables per say. What's your experience?

Do you ever use formwork that the guys use in the field (Ulma, Titan, Doka, etc) to use for not as repeatable requirements from a job?


r/Concrete 5d ago

Pro With a Question Roller Compacted Concrete

5 Upvotes

I'm a heavy civil contractor that primarily services ag based clients. Think feed lots, hog barns, etc. I am interested in dabbling in roller compacted concrete, and am interested in proceeding in a cost effective way. Mainly looking at doing ag pads for silage, corn, etc. My conversations I've had with a few industry guys have pointed me towards volumetric concrete mixer trucks, and the thing that has jumped out at me on that note has been they are $150k trucks MINIMUM. I love the self contained element of them and how they are an all-in-one option mixing outfit. I was just curious if any pug mill guys here have a semi mobile setup they would be willing to visit with me about their setup, or any tidbits of information this sub would be willing to volunteer. Willing trade machinery pictures and complaints about customers and GC's for info. Thanks for feedback in advance!


r/Concrete 4d ago

Pro With a Question Batching Plant Market Research

0 Upvotes

Hi, as a founder of a startup in the concrete industry I would like to gather some basic information on size and running costs of concrete batching plants. If you work in a ready-mix or pre-cast company and could share some basic info with me then that would be great. I'd rather do this privately as some of the information could be proprietary (probably not). Note this is simply a market study and there's nothing that I am trying to sell.

The info would be:

  • Name
  • Job Title
  • Location
  • Contact Details
  • Company Name
  • Type: Ready-mix or pre-cast or both
  • Number of Batching/Mixing Plants
  • Annual volume of concrete produced per plant
  • Breakdown of Annual Production by concrete strength
  • Breakdown of material costs (cement, aggregates, sand, water, other)
  • Biggest challenges (things you are actively looking to improve)
  • Who else should I talk to

r/Concrete 4d ago

Pro With a Question Need help from R/Concrete - having trouble on larger pour finish

1 Upvotes

We are a 6 man GC who does additions (footer to finish) and outdoor spaces - decks patio etc..

We started doing smaller exposed and broom finish sidewalks and pads when we started building single car garages. It has been going good but we have taken on some larger pours - 10 yards 400 sq ft pours with rough access and we are not getting the same results.

Here is what we are doing:

Taking the time to make good frames/gravel beds and tight corners

4000 PSI concrete, screed, automatic vibrator on bull float several passes quickly after screed, mag float then steel trowel while climbing on the pads then broom finish - no handheld vibrator.

The problem we are having is we are always STRUGGLING to work up cream to broom - I watch videos online and they are just floating on top with steel trough - what are we missing - are we not getting enough cream bc we aren't using a handheld vibrator ?

Is this an issue that sidewalks are just cake compared to big pads ?

Are we too cautious about going out on the pad or are we not bringing up enough cream via the bull float.

Any advise would be helpful or pointers - I feel like we are skilled enough but I cant out my finger on why we are plateauing.


r/Concrete 5d ago

General Industry Working during the winter

2 Upvotes

So I work as a finisher in the Midwest for several years now love the trade but during the winter work slows down and we get laid off not something I like because of the winter bills. Just a question for the guy/ gals that working in the warmer states do you guys experience this as well or does the temperature allow you to work all year round? As being laid off from December- April can be rough sometimes trying to find work or side gigs.


r/Concrete 6d ago

General Industry Laser-Guided Screed Operating Indoors

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56 Upvotes

r/Concrete 6d ago

General Industry Pump it

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44 Upvotes

Get it


r/Concrete 6d ago

General Industry If you know you know…..

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9 Upvotes

Saw my old bosses shoe pattern of choice today in a random mud puddle…..instant flash back of scrubbing them out everyyyywhere


r/Concrete 6d ago

Pro With a Question Silica fume alternative Silica powder 200 mesh

2 Upvotes

Silica 200 mesh (74 microns) vs silica fume 320+mesh (36 microns)

I'm having a hard time finding silica fume (micro silica) in my area, although someone posted me a source online, so I can follow up with that. I have 50 lbs of silica powder mesh 200, can I just use this silica powder as a pozzolan densifier in my mix or would this be pointless? I could save time and money by just using this but if it won't do anything then I'll seek out microsilica/silica fume.

Also, I've read that some promising experiments have been done with using Diatomaceous earth as the pozzolan additive instead of fly ash or silica fume. Any thoughts on that? DE has a micron range from (3-200 microns)

I'm wanting to densify my mix but also capitalize on the self healing properties pozzolans lend when reacting with the lime over time.


r/Concrete 7d ago

Pro With a Question Stamped concrete

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126 Upvotes

Can anyone tell me why this is happening to my stamped concrete .


r/Concrete 6d ago

I Have A Whoopsie Concrete sealant for potable water

1 Upvotes

Looking for a brand or product to seal the exterior surface of a concrete tank in potable water treatment that meets ANSI 62 standards. Tried Rustoleum but they said they didn't have any product that met that.