I don’t think any AASHTO roads are 24ft wide, the minimum is 28ft. That includes 2 traffic lanes plus margins or shoulders on both sides. The margins vary in width in different models, but I believe 2 adjacent lanes are always 24ft. I don’t recall seeing any AASHTO roads without margins, at least not on the DLS. I can’t speak about 3rd-party web sites as I never use them.
The crack- and patch splines are 24ft wide because I wanted them to fit over the traffic lanes only, not to extend into the un-trafficked margins. They are not roads, they don’t generate or support traffic, but are just cracks or repair patches on a transparent background. I figured this size and configuration would also give them the best chance of being usable with many of the non-AASHTO road types available in Trainz.
The crack- and patch splines all have names starting with “AASHTO 24ft....” so they would group together with gfisher’s (and slabay’s) AASHTO roads in Surveyor. This makes them easier to find when you’re placing roads but wasn’t meant to imply any of the roads themselves are 24ft wide. I hope I’ve covered everything.
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