Dear Tyler, you're so great. I wish I was young and you could be my teacher, then I could finish as the God of concrete.🤪

I like to make saw cuts at inside corners. I hope to see more basalt or fiberglass rebar in slabs, along with emphasis on compaction and curing for longevity. Concrete should last hundreds of years. My question is what can be used for tie wraps, that will not be subject to expansive oxidation.

Thank you answering my questions on corners!

Great information! Thanks!

Love your videos! Thanks for the incredible info! 🙏

Woohoo! Another awesome video. Who knew learning about concrete could be so fun.

Putting in a grain bin, and have been researching/building the foundation to death. It's amazing how little reinforcement some people will put in. I settled on a 3x3 grid of #4 for the footing, which is going to be 2' wide, and 15.5" below grade on average (shooting for 12" below grade on low side as there is a slight slope), and 24" above grade. The interior "pad" or slab will be 8" thick, #4 rebar 12" OC. 16" of 3/4 in. roadstone for fill of the pad area, interior form for backfill to hold it in place and achieve a 90 degree angle, and will be moistened and plate compacted. Person I talked to for my diameter bin recommended a 2x3 grid for footing, and 24"OC for slab, so hopefully, I overengineered it enough. Also adding verticals to support the footing grid, and perpendicular cross pieces of rebar between for each set of 3 rings @ 12" OC. For a 21' bin(which is also the center of the footing), I'll use a little shy of 2000 lbs. of rebar. Hopefully its enough. :D

Superb sir, I learn a lot from your presentation. Thank you.

Professor, I think you math is somewhat off: 2% of 3m (300 cm) would be a 6 cm slope, not 12.5mm or 1.25cm. Or in imperial: 0.2 feet (2 13⁄32 inches). What you are proposing is more like 0.4%

A half inch on 120 inches is just over 0.4% slope.

Have to get one of those shirts!!!!

Hi from Türkiye. Thanks for the videos :)

Facts

You mentioned you’d be putting out a video on the technical level regarding vibration. Vibrating tables for pavers, loading of tables, force requirements, newton, frequency etc.

Nice Videos

Keep up!

Hello dr ley, please make a video about your favourite books on reinforced concrete design. Thanks

Control joints off those corners, great point w the 2 rebar, done that b4

Self-healing concrete (SHC) is the way to go. My great great grandfather swears by it.

thank you for mentioning sloping the concrete away from the building. so many just do flat walkways etc and it causes water to run back into the building causing a lot of problems. you also have to keep in mind that many walkways/driveways end up being overland paths for storm water in big rain.

I absolutely hate wire mesh. I have never seen it end up anywhere other than the bottom third of the mat, and over fifty percent in direct contact with the soil. If the mesh is supported enough that it isn’t going to be stomped into the bottom of the slab, it is more efficient to install rebar on chairs. And if you design the rebar installation at the upper third point, it is very hard for the workers to stomp it down past the mid point.

They sell the wire mesh, or as I've always called it, welded wire fabric, with deformed wire as well. I can get it in a 6x6 grid with 3/16 wire thickness here in NC, in sheets of 5x10 or 5x20. This saves more vertical space than #3 rebar would. If I used rebar in my composite deck slab, that would push the hydronic lines uncomfortably close to the slab surface --counting the deck with its corrugations in a 4" overall slab thickness. WWF is also more convenient if you're going to run hydronic lines. There are more anchorage points than an equivalent grid of rebar. One time I had set the beams too high resulting in a vertical distance to the screed edge of about 3.5". The concrete guy came and poured and floated. But when it came time to trowel, he gave me the option: He could either power trowel and risk pulling up a hydronic line, or he could stop there. I had him stop. Now I have a rather "rustic" floor. One problem with the wire mesh though: If you lap them the way code wants, then the lapped corner intersection of four sheets is going to stack 8 wire thicknesses high. 8 x 3/16 = 1.5" in my case. So I cheat and cut out some of the wire forming the stack. Update: Man, never commit to buying WWF without seeing it first. Retailers typically stack it outside for years until it sells. My most recent batch has rust just short of pitting. I thought about returning it, but the particular slab I'm doing won't be exposed to the elements, else I'd worry about eventual spalling.

Please make a presentation about upper floor concrete slabs (not ground floor because you've covered these). How to prevent or at least minimize cracking. A new building near me that I'm aware of has diagonal cracks along all the corners of the second floor slab.

Informative video. Viewers should know the slope calculation near the end is wrong, as as others have pointed out.

Curious about the 'chairs'. No doubt they are left in the pour ,but do they too not cause problems like the re-entrant corners ? I would think we end up with stress points there ?? Does the concrete naturally stick to them ? Can you suggest specific macro fiber products ?

Spalling is a major problem in our area. (Buffalo, NY) driveway contractor blamed it primarily on bad aggregate. Even more than salt. I picture the bad aggregate deteriorating, swelling, and popping off the thin cement above it Comments?

2% slope on 3 m long side is rather 6 cm than 12,5 mm (like it was shown) - am I wrong?!

I met my first girlfriend on a concrete slab parking lot before seeing Concrete Blonde in concert. Thank you, concrete!

Thank you for your inspiring video. I was wondering how to solve the shrinkage problem of the 3D printed concrete since there is no coarse aggregate.

Also, how about a round hole when possible- like for a sump pump. No corners, no stress concentration.

Why do you recommend specifically two rebar at reentrant corners? I usually only see one, but is there any advantage to two bars instead of one larger bar?

What's your opinion on asbestos fiber? Do you know any way for it to be safely used in field situations and no just precast?

Soo what if I have cracks that I wish to prevent from worsening? Can they be sealed? Thank you for all the great videos!

Mr. Tyler, can you give us tips about concrete terrazzo slabs ? What should we pay attention to pour slabs like 2-2.5cm thick

Do macro fibers present a problem of wicking in surface moisture?

Bars in “Upper” part of slab? I thought lower parts?

Do you have any vid on graphene in concrete

Where do steel fibres like Helix or Dramix fit into this? Are they treated the same as the macrosynthetic fibres or are they not as good or perhaps better?

Why is the rebar/remesh in the middle or upper third of a slab? In a beam the tensile stress is at the bottom, unless its cantilevered, so it seems sensible that the rebar should be in the bottom third of a slab when thinking of the tensile stress being greatest at the bottom surface. Also, consecrators commonly 'cut' the upper third of the slab, wouldn't this cut hit rebar then?

What if the hole is not squared but round. How do you reinforce a circular void within the slab (e.g. for a circular column, or other circular feature in the slab).?

Do you have a video about or would you comment on this new "dry pour" trend I have seen popping up on KZfaq lately? Where they just dump dry premixed concrete into a form, then mist it on top. I can see several downsides, but If it is in a temperate climate with no freezing temps would this be a reliable method in certain situations?

Can you able to make p-m intraction curve for t-shaped ? ..

What about rounding the interior corners to break up the stress concentration in placeof extra rebar?

Nice. This might actually be of use to someone. Rock on

ACI code is .03% of cross section area should be steel .. Minimum I recall. Fiber is the ticket. But can hamper finish operation.

How can I share the actual site images?

How to avoid the cracks as attached in the photos

2% = 1/4 in per foot when grading away from structure

Is fiber reinforced concrete more fire resistant than rebar?

Yoda has spoken.

I have been in the slab business for years and as of late I see fiberglass rebars.........I picked up a single piece and instantly put it down like it was a cursed item........I could never see myself using it for any purpose........can you tell me why this was even Invented

Since when is a 1/2" drop over 10' a 2% slope? Is math different in Oklahoma? 1/2" = 0.5" 10' = 120" 0.5 ÷ 120 = 0.00417 Or less than 1/2% slope. For a 2% slope we use 1" per 4'. Granted 1" per 50" would be exactly 2%. But 1" per 4' is 1" per 48" which is really close. Another example is a 4' wide sidewalk. Set up one form and inch higher than the other and you're there.

It's 4.167%

2%*3000mm=60mm

Hello freaks and maniacs ✌🖐

Do you really think you can teach amateurs in a eight minute video what takes us professionals years to learn? Concrete is demanding. Everything about it has to be done just right because you only get one shot at it. Can you teach these guys the codes that pertain to everything concrete? Can you tell them how to put an acceptable finish on a piece of concrete? Can you teach them how to pour and finish a quality piece of concrete? You can't can you. What a joke.

Please help out… when you say the rebar goes in the center or the slab, is that not the zero for bending moment in tension and compression? So if a load is applied to the slab, would this rebar serve any purpose than for cracking?

less water equals?... does shotcrete equate to stronger concrete?...