Compliments of the season to one and all,

The slab of my house is one-piece, poured concrete with rebar reinforcing. The garage floor is the original poured concrete surface.

When I park the car having been driving in the rain, inevitably, pools of water accumulate around the wheels, and of course, do get absorbed into the concrete.

To date, there is no evidence of the rebar rusting but is there anything I should be doing to prevent it rusting? Or after 12 years, is it already too late?

Thanks and toodle pip

Concrete is very alkaline and that protects the steel from rusting, there are plenty of reinforced concrete structures 100years old or more.

It doesn't like sulphides or chlorides much, but as you are not spreading rock salt on it, then no problems! The concrete wartime sea defences are still intact on the beach near here, despite the salt.

I think where the salt runs off wet wheels it will soak into and accumulate in the concrete - I would park on small matts to prevent or reduce this problem. It is not something to worry about though,

Your indoor garage floor is going to have a very sheltered life with next to no potential for corrosion. There are millions of domestic garage floors in use every day without any precautions. There really is nothing to concern you.

Mind you a decent garage floor paint (ideally 2 part epoxy) is a good idea to make it easier to clean, it also reduces dust and dirt getting into the house if you have an internal door to your house.

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More generally - Structures exposed to the weather do just fine with 50mm of cover. Internal concrete usually has 35mm cover but that's more about having enough space for the aggregate to get past the reinforcement when the concrete is poured.

Corrosion of reinforcement can occur most commonly due to inadequate cover in an area of high weathering. Other factors include excessive chlorides (ie salt) or carbonation (ie atmospheric indutrial pollution). These require very high levels such as a sea spray, motorway, or heavy industry.

IMHO "Concrete cancer" is specific to alkali–aggregate reaction which is caused by impurities in the aggregates that resulting crumbly concrete. Wiki has a good page explaining the chemistry of the most common version called alkali silica reaction https://en.wikipedia.org/wiki/Alkali%E2%80%93silica_reaction

The problem with mats is that if water gets under the mat it can take ages to dry out so putting a mat down is likely to keep the concrete wetter for longer.

I used off cuts of vinyl flooring under each car wheels to stop hot tyre pickup. This is when hot car tyres would stick to the concrete and pick up a bit of the surface each time. Trivial amounts and only cosmetic but you could see a worn patch when the garage was empty.

The mats do also catch drips of dirty water from the wheel arches in winter which makes things a bit cleaner.

@revor "the environment remains humid and vehicle does not dry out properly"

Ventilate the garage?