[Retric]

22 tons are huge busses and overkill unless you actually need that much space, and tend to have 4 axles. ((22 / 4)/(3/2)) ~= 13.5x a heavy SUV but could be replacing 30+ vehicles.

Also that visible ware is noticeable because it hasn’t been replaced. Looking worse when you resurface on the same schedule isn’t an actual cost.

[coryrc]

But those are what we have and they have 3 axles, not 4.

We also have many concrete roads and closely-spaced axles, if they had them, would not help.

> Looking worse when you resurface on the same schedule isn’t an actual cost.

I addressed this: they have to dig much deeper and replace with much thicker road. Much more expensive. It's not "looking worse", it's actively dangerous to cyclists and other road users, so the surface must be replaced more often too.

[Retric]

Closely space axels work fine for road surfaces they don’t help on bridges but that’s a separate concern. You can see a plethora of heavy military vehicles etc which use extra axles to avoid getting stuck in the mud due to plastic deformation IE rutting. EX: The 22 ton KTO drives has to deal with rutting on vastly worse road surfaces like mud. https://en.wikipedia.org/wiki/KTO_Rosomak

But this is where you need to do a deeper analysis than just a simple rule of thumb. Even adding extra wheels to the same axle makes a big difference to road surfaces.

> so the surface must be replaced more often too.

Level of ruts you see are considered acceptable or they would be replaced.

However, ultimately the same entity is paying for the busses and road maintenance. If lighter busses saved taxpayers money that’s what they would use which is a major sign your analysis is inherently flawed.