I would suspect in part that it is due to lack of accurancy with laser survey measurements (human fault factoring) and it is sometimes due to a change in how runways are measured over uneven terrain. Just a guess.
My understanding is that our pavements don’t get the “kneading” action that streets and highways do. Traffic moving on roads,changing lanes etc,keeps the oils kneading through the AC. Our pavements are much larger,with portions of the surfaces never getting any traffic at all.
The shoulders at RNO are asphalt and the shrinkage on them amazes me.
LOL—couldn’t agree more on the “amazes me” remark. Both high traffic volume and low are susceptible to shrinkage, especially in freeze/thaw locations. Moisture is certainly a factor once it breaches the surface.