The powder I add was developed 20 to 30 years ago in Japan to make structurally sound self-compacting concrete.
By a happy coincidence, it makes a waterproof mix of concrete - that would be too stiff to move let alone compact - WATERPROOF because it makes it fluid enough to get all the air out.
What happens when you put twice the dose of powder into waterproof concrete?
Here are 3 videos. Very short. 9 seconds, 8 seconds and 7 seconds. YouTube video 1. YouTube video 2 YouTube video 3
Both pours in the videos are the ground floor over a basement.
One of the ground floors will be a patio with basement beneath so the far side is waterproof concrete with double the dose of powder.
The majority of the ground floor will be inside and not waterproof. After the first load, the rest of the concrete was was a C40 pump mix S3, which is a standard structural concrete, and you can see the difference in the finish.
This has double the powder. Waterproof, structural concrete virtually self compacting.
This just has the readymix concrete supplier's additive. Structural concrete. It flows without my special admixture because it is made with more water, and that is why it cannot be waterproof.
My admixture normally costs £29 to treat each cubic meter of concrete.
If you want me to double the dose I can give 10% discount.