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AI for American-produced cement and concrete

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Re: AI for American-produced cement and concrete

#101

Post by somerandomqaguy »

givemeethekeys wrote: post #83
sidewndr46 wrote: post #45

Earlier quoted context omitted.

Glad to see someone pointed this out. The test consists of a bucket, plywood board & a stopwatch.

Seems simple. Is it effective?

Reasonable so, slump tests have been in use for as long as I can remember. There's a couple of other tests that need to be performed as well for fresh concrete. One for air content in the concrete, then temperature and volumetric weight.

IIRC the big tests that occur are the cylinder samples that are taken as well of the concrete and allowed to cure to full strength before destructively tested anywhere from a week to a month after pouring.

Re: AI for American-produced cement and concrete

#102

Post by mschuster91 »

datsci_est_2015 wrote: post #98
GorbachevyChase wrote: post #94

Earlier quoted context omitted.

It’s customary to prefix these comments with credentials, so I’ll just say that I’m a roadway engineer. Sampling at the batch plant or even at the truck is not going to give you the whole story. While the most common crime of contractors is to overwater the concrete slurry to make it flowable, other problems in workmanship can arise from failing to vibrate the concrete in its forms, leaving voids, or vibrating it too…

“it’s just not that simple” - my career in industrial data science in a nutshell. Lots of large companies come into the domains I’ve worked in with grand promises, and while sometimes they move the needle in terms of what executive leadership within the industry believes is possible, they also often poison the well for us smaller firms who provide much more leveled and concrete (heh) offerings. Curse IBM, for example…

AI is just the same. CEOs all over the world have fallen to the lure of the AI grifters, believing they can fire people en masse now and ride it out with the remaining staff until AI catches up with the remaining 20% of capability.

Small focused AI/ML companies however that don't deal in LLMs? They struggle to find customers, even with stuff that clearly works, because they hit the wrong buzzwords.

Re: AI for American-produced cement and concrete

#103

Post by elictronic »

seemaze wrote: post #25
alephnerd wrote: post #11

Earlier quoted context omitted.

Most large scale DC projects I've know are primarily leveraging solar with grid batteries because of the low upfront cost and state incentives.

Apologies for the sarcasm. I appreciate the drive for renewables the current AI DC buildout brings with it. I have real fears that building materials will experience the same inflationary pressures computer memory is currently experiencing. The U.S. TSMC and Intel fab construction alone in the last couple years has had an outsized impact on building costs.

The US construction industry does about 3 trillion in revenue per year. Those two fabs are something like 20 billion per year. 2% is a lot but markets can handle that just fine. Local markets will have higher prices.

Re: AI for American-produced cement and concrete

#104

Post by mschuster91 »

munk-a wrote: post #69
Animats wrote: post #28

Hand-held devices for testing concrete properties would be more useful. Most concrete problems come from a bad mix - too much water, not enough cement, etc. Concrete testing usually involves cutting a core out of the poured slab and sending it to a lab. Something where you stick a probe in the mix and can reject it before pouring would help. Here are some on-site concrete testers.[1] They're heavy and a pain to use.…

> too much water, not enough cement, etc. I wanted to mention that Concrete is far more complex and regional than folks might imagine. The quality of gravel and sand, local impurities - these all contribute massively. It's probably best to think of it like a wine's terroir - except, unlike a bottle of wine, it's prohibitively expensive to ship both the components and the finalized mixture to different areas. If a reg…

And it's not just the gravel/sand that's important. The water itself also differs in its chemical composition (e.g. salts, minerals, basic/acidic pH), which can catch you really dirty when making concrete. Or when dealing with water at all, shout-out to Flint and its infamous water crisis that took eleven years to resolve - every single lead service pipe had to be physically dug up and replaced.

[1] https://en.wikipedia.org/wiki/Flint_water_crisis#2025

Re: AI for American-produced cement and concrete

#105

Post by quickthrowman »

bluGill wrote: post #86
harimau777 wrote: post #32

Earlier quoted context omitted.

I'm surprised the ratios for a given situation isn't standardized by now. Is it just people cutting corners?

My grandpa used to be a concrete inspector (for the state of Minnesota - if you ever drive i394 there he was one of the inspectors for that). Different plants within a normal commute of his house often had very different sand and so needed a different mix.

Oh cool, did he work for MNDOT? I sell and run a lot of work at their facilities, they have a materials lab over in Maplewood off Hwy 36 and English St, and also the weird test surface area on 94 west of St Cloud.

Re: AI for American-produced cement and concrete

#106

Post by quickthrowman »

hedayet wrote: post #74

Only (April) fools would trust Facebook's technology with anything as safety critical as construction work.

Meta spends a ton of money on concrete, a 1M sqft data center with a 6” slab has one yard of concrete for every 54 sqft of floor, which is around 18,500 cubic yards of concrete.

Any improvements to concrete mixes will benefit them.

Re: AI for American-produced cement and concrete

#107

Post by cyanydeez »

bluGill wrote: post #82
munk-a wrote: post #69

Earlier quoted context omitted.

> too much water, not enough cement, etc. I wanted to mention that Concrete is far more complex and regional than folks might imagine. The quality of gravel and sand, local impurities - these all contribute massively. It's probably best to think of it like a wine's terroir - except, unlike a bottle of wine, it's prohibitively expensive to ship both the components and the finalized mixture to different areas. If a reg…

> it's prohibitively expensive to ship both the components and the finalized mixture to different areas. We could do this if it is important. There are mines in Wisconsin the export sand to the middle east because that is known to work well for fracking and they don't want to risk a local sand not working well. (AFAIK they have never tested local sand properties, but it is possible they have and it doesn't work). In…

for fracking, what they want is a perfectly uniform sized quartz grain thats rounded. You find this sand where multiple processes occur, notably glacial geology. You want uniform grains because frackings goal is to open, then support an porous structure when you can then pull the fluids/gas out without clogging.

It's not really hard to test for this property, but the cost efficiency is notable when you find a massive amount of it in one place. It still may be washed to remove further silt/clay, but they absolutely know the product works and they generally know the geology in other places don't tend to produce the same material.

There's a fair amount of materials size thats mostly "we found this geologic material and this is some magic shit" rather than some wholly manufactured human endevour.

Re: AI for American-produced cement and concrete

#108

Post by bluGill »

quickthrowman wrote: post #105
bluGill wrote: post #86

Earlier quoted context omitted.

My grandpa used to be a concrete inspector (for the state of Minnesota - if you ever drive i394 there he was one of the inspectors for that). Different plants within a normal commute of his house often had very different sand and so needed a different mix.

Oh cool, did he work for MNDOT? I sell and run a lot of work at their facilities, they have a materials lab over in Maplewood off Hwy 36 and English St, and also the weird test surface area on 94 west of St Cloud.

Yes, drove snow plows in the winter from Chaska (no longed there). He retired long ago.
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