I am interested in setting up a diorama for my nearly complete Revell 1/32 scale JU88 A1. I was thinking of having the base split maybe 60/40 tarmac to earth/grass; at an angle to the base. Most tarmac is constructed using perpendicular expansion joints between the concrete pours; resembling squares or rectangles. Did Germany in WWII have a standard for the distance between each expansion joint? Or is it even realistic to do a dio scene using concrete tarmac? I see so many pics of German aircraft parked in a grassy field vs. a taxiway, etc.
There seems to be tarmac options for 1/72nd or 1/48th scale; but not for 1/32. One idea I got from another forum is to use a fine grain sandpaper cut to the correct dimensions and painted/weathered to resemble concrete. So that is the route I will likely take. Just need an idea of dimensions to fit 1/32nd scale. Thanks!
Pics of WIP:

