Sand and macadam for self-mixing

[hul]

Are there any disadvantages to increasing the coarseness of macadam other than it being more difficult to handle?

Yes, among other things, it must be able to pass the tightest measure easily, which is usually between the reinforcements. This can result in poor encapsulation around structures.

There is a whole section in the concrete course on how to calculate the correct Dmax.

Dmax = largest stone size (slightly simplified)

 

[justusandersson]

Is there any disadvantage to going up a gauge in macadam other than it being more difficult to handle?

I don't think so.