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Tangentially related, but there is a new generation of trucks that mix the concrete on-site. They can output small batches and change the mix on the fly. They solve a lot of headaches!

https://cementech.com/volumetric-technology/


This may work on a small scale, not in most commercial use cases. A typical deck pour (400cy) will pour at 70-80cy/hr. you got 9-10cy/truck. Meaning you have 7 to 8 minutes to back in the truck, empty it into the hopper and leave. You barely have time to add water to the mix. Most high-volume concrete plants are "dry-batch", which means all the ingredients get dumped into the drum and the concrete will get mixed while driving to the project site. Also, changing mixes on the fly will not "fly". No one is going to authorize the adjustment, because what happens when the mix doesn't meet specs... It will need to get chipped out.

The target audience of these trucks is sub-10cy jobs. It allows companies to cater to smaller customers at a premium.

In the large road projects I've seen they bring a concrete plant to the job. Buildings still get trucks coming in.

I highly recommend the 9 episode miniseries podcast The Big Dig from GBH. Their mismanagement of the concrete was wild.

Concrete mixer trucks are not new at all actually, they've been around for a long time.

Traditional trucks pick up cement from a facility and rotate it to keep it from setting. They don't mix it on the fly. Any extra is considered waste is poured out.

Where did you get the idea that rotating is "to keep it from setting" and not mixing?

https://en.wikipedia.org/wiki/Concrete_mixer#Concrete_mixing...

"Special concrete transport trucks (in-transit mixers) are made to mix concrete and transport it to the construction site. They can be charged with dry materials and water, with the mixing occurring during transport. They can also be loaded from a "central mix" plant; with this process the material has already been mixed prior to loading. The concrete mixing transport truck maintains the material's liquid state through agitation, or turning of the drum, until delivery. "

Y'all both right.


It worked for Fox News


A study from 2023 estimated a worst case blackout in Phoenix AZ could approach 1% fatality. Considering power demand would be at its highest during a heat wave, the odds of this worst case scenario are quite high.

https://pubs.acs.org/doi/10.1021/acs.est.2c09588

"In Phoenix, where the lowest daily high temperature over the 5 day heat wave is 43 °C and daily minimum temperatures average 32 °C, the rate of heat-related mortality increases by about 700% relative to the Power On scenario, reflecting the extremity of heat exposures in a desert city in the absence of mechanical AC. As reported in Figure 3, the estimated rate of heat-related mortality for the Power Off scenario in Phoenix is 917 (approximate total =13,250 deaths), which approaches 1% of the synthetic population."


AZ better ramp up subsidies for home-installed solar then. When conditions are worst, they receive the most relief!

https://resilient.az.gov/resiliency-programs/energy-programs...

"The Office of Resiliency received a termination notice from the U.S. Environmental Protection Agency regarding the Solar for All grant on August 7, 2025. The program is unavailable until further notice."

Or they can wait for the worst case scenario to actually happen, and THEN do something, as is tradition.


What did people in Phoenix do before modern heat pump air conditioning existed? Plenty of people live in hot arid places on earth. Humans have figured out passive air conditioning since prehistory: https://en.wikipedia.org/wiki/Air_conditioning#History

The problem with cities like Phoenix that is people are used to high levels comfort while building traditional structures in the middle of a desert. To cope, electricity hungry industrialized HVAC systems fight the desert weather. With a daily hot/cool cycle and modern thermal management you'd think the "passive house" would be law there by now.


Yeah; loss of utility heat in the wither has a much higher fatality risk, I'd think. The difference is, many homes have multiple heating methods available to them. If the natural gas is out, use an electric spaceheater, for example. Some homes use electric heat, others natural gas, others heating oil (which is a distributed solution.. or at least, involves a caching layer!)

Many homes have fireplaces or wood-burning stoves, again, for backup.


OTOH typical heating in North America is forced air natural gas. So if either the gas or the electricity is down, you have no heat.



The thin strip of yellow/black caution stripes on an otherwise unnoticable green conduit was so ironic it made me smile: https://en.wikipedia.org/wiki/Go_Away_Green#/media/File:The_...

It's saying "DON'T NOTICE THIS! (also, please notice this!)"


A gas station near me painted their bollards this color. I've wondered if this would be a credible legal defense for someone that accidentally backed into them.

Go Away reads to me as a command to the viewer to go away rather than the intended "we want the object to go away from the viewer's thoughts". If they were okay with a phrase like Go Away Green, why not something like Hidden View Green, Irrelevant Green, Don't Look Here Green, etc. Some PR department would have a field day

Prob because Go Away Green sounds way cooler than all of those and it’s not a user facing term anyways.

And alliteration for extra cool.

"Move Along Green"

I've said it before on HN, but I just want a somewhat trustworthy group to develop "DUMB" certification. I think enough people would pay extra for a certified DUMB TV for it to be worthwile. "Don't Upload My Bits"


Reminds me of the coastline paradox - https://en.wikipedia.org/wiki/Coastline_paradox


It's wild that people were forecasting this last night because troops were posting photos of lobster dinners.


It is a bit similar to Vietnam in that it is a step-wise increase of committed troops. Whoever is really planning this war, is now pushing for more and more "boots on the ground". It is almost as if Trump does not even have any other choice now. Reminds people of Putin - Putin is also stuck in the war against Ukraine.


Putin could have frozen the frontline a month or so in and declared victory. That probably would have been a smarter move there.

I'm not so sure in Iran.


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