alt Hacker NewsDo you know how they keep the concrete from cracking? All the pads in general are in way better shape than my driveway, and the driveway has decent support underneath and is subjected much, much less load.
Maybe they use plentiful jagged interlocking sharp granite as the base l? (like railroad track foundation)
Next time you're at SFO, SJC, or any other major hub sitting in the plane before it backs out of the gate take a second to gaze upon and admire how pristine all the concrete pads are, it's really impressive.
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Not sure if that's a serious question, but your driveway might lack a proper foundation, so the surface is moving and cracks. Also, it's likely not concrete, but tarmac (which is much softer).
Mostly the extensive subgrade work, as I understand. Similar to a road, there’s a bed of sand and aggregate under the concrete surface.
The concrete they use is very precisely mixed to a specification and then it’s tested for adherence to the spec.
A runway is also going to be 3-4x thicker than a 4-6” thick driveway slab. Probably they also use fiberglass or PVC coated rebar instead of plain steel rebar.
Definitely not an expert here but I can read a civil site plan and hire civil site work subcontractors frequently.
Here’s some information on concrete testing: https://www.concrete.org/frequentlyaskedquestions.aspx?faqid...
Also, Grady is one of the best creators on YouTube, I can’t help but watch his full videos whenever they pop up. I always learn something, even if I’m familiar with the subject.
Edit: Granite is not one of the listed materials in Part 4 - Base Courses of the FAA runway construction guide, here’s the entire thing for reference - https://www.faa.gov/airports/engineering/construction_standa...
If I had to guess, all things equal, its probably much thicker than your average driveway.