Actually, the rotation is mainly to keep the concrete well mixed and homogeneous during transport, thereby insuring the sand, gravel, water, and cement is well mixed. The concrete itself will set up...
About 8m^3
Silica flour and Silica sand our admixtures to Portland cements.
not very long it takes about 3 or 4 hours 2 dry but wont be fully done until the next 24 hours or so
a hardened criminal