Chris, what I've always used for the collar is 'driveway mix', ie, the same stuff the ready mix co would send out for pouring a driveway. The stuff I've seen usually has 3/4" gravel (a/k/a # 57 stone) and has a strength of ~ 3500 psi when set. As for slump, it depends on whether you have large voiids under parts of the pannels and how far you'll have to 'drag' the concrete ( I usually shoot for a 5 -6 " slump, but will adjust that # depending on circumstances)
I don't want to take up too much space/ time but, if you have any ?s about how to do it, or things to watch out for, just post it here and I'll tell you what I know. Sounds like the project is progressing![]()
![]()
Bookmarks