The job I mentioned bis a bit weird.
It's an office in a Ford dealership.
It's the "bosses office"
It's Oregon's oldest Ferd dealership. Actually I have known the owners for 30 years.
The office is adjacent to a sidewalk. Problem is, the room is 5 inches
below the level of the sidewalk outside.

The room has a wood floor on sleepers................... 2x4's layed flat on their sides, then 3/4 inch treated plywood screwed onto that.
The initial problem was the old plywood got soft and spongy........... meaning water was getting in.
We carpeted this office 20 years ago.
OK, so the handy man tore out the old carpet and plywood floor and what we saw was a bit ugly.
I ended up scraping, wire brushing, making concrete forms to seal out water. Way over my pay scale............... but it had to get done.
This is the outside wall, viewed obviously from the inside. I needed to make a concrete form about 6 inches tall to get above the sidewalk level outside. That will keep water outside from traveling down into this office.
Never in my life have I seen a pour like this. BAD!
I removed a lot of loose rocks and was literally digging out sand so I could pack concrete into the void as far as possible so water couldn't intrude from below ground level.
You see, ..........we have a big problem here. Downtown here is just a few feet above high tide.
So if you add together, high tide coinciding with heavy rain, plus the vibration from log trucks traveling next to the business........................... It's almost like liquefaction, .....literally pumping water into this office. ......not always, and not in the summer and maybe just at high tide when accompanied by a lot of rain. We are
hopefully fixing a problem based on guesses and first hand analysis. IE: crap shoot
The image after the large river stones is the concrete form in place.
Lastly is the form in place and filled with concrete.
I made a concrete vibrator using a Makita square sheet sander and some 1/4" steel bent to shape. Touched the sander to the rod and the vibration was amazing. Amazing how quickly the poured concrete settled, shrink then disappeared below the top of the form.
Once vibrated, I just added more to bring the level back.