My grandpa worked on the PA Turnpike and he said they had the technology back in those times to put macadam/cement down for 50 years or more but the politicians saw an opportunity to have Union labor on a continuous basis holding on to a job at taxpayer expense. This was 60 years ago,so I could not verify.
Yep, they’ve had this capability for years, especially with ashphalt but because it would mean the loss of so many jobs no union crew would touch the stuff.