vtsnowedin
Elite Member
I'm not fighting just talking. I started working for the NH DOT in 1975 and retired from them in 2006. I started out as a soil test technician and concrete plant inspector and ended up as a contract administrator doing interstate rehabilitation contracts which were primarily paving jobs. I had jobs with as much as a hundred miles of secondary road resurfacing using a sand mix placed at just 300 tons per mile (3/8" nominal depth). Specs in Florida are a lot different From New England due to the difference in the weather and local soils and aggregate availability as well as a good dose of politics on the state and Federal level. The super pave specs were developed and modified with as much politics as science applied at the federal level.I'm not trying to fight; just worked for 4.5 years as a county engineering inspector, inspecting roads and road construction.
I've seen several things come and go as they came in or out of political fashion. It's sort of like hemlines on skirts.
In New England we would never consider adding any clay above sub grade or use any rock that had an LA wear of more then 50 percent. There is good hard (20 %LA wear) rock in almost every town so there is no point in using soft or rotten rock for anything except fills four feet or more below finished grade.
Florida specs work fine in Florida and I do understand how clay can be beneficial with the sands your mixing it with but the Asphalt paving industry has had a great success promoting thick layers of pavement were thicker layers of properly constructed base courses would have been cheaper and more durable. The New England states have drunk the koolaid as well pushed from the Federal level so there isn't any yours is better then mine to point to.