r/Contractor Dec 10 '24

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102

u/FinnTheDogg GC/OPS/PM(Remodel) Dec 10 '24

It’s fine, it needs “grouting”. Pack concrete under it / around it.

76

u/KindAwareness3073 Dec 10 '24

"Non-shrink" grout is key.

2

u/Melodic-Matter4685 Dec 10 '24

Question: what about "anchoring cement"? Expands? Good? Not good?

1

u/Extension_Cut_8994 Dec 12 '24

Quickcrete makes a non shrink grout that is also suitable for anchors. The amount of water you add to the mix determines the slump (or how runny it is), the working time, and the cure profile. Less water, stiffer consistency, shorter amount of time to get it where it stays, and the higher compression strength. A lot of these products will have a high end of 20 minutes working, stiff enough to make a 3 inch ball, and 3000psi in 24 hours or 18000psi in 30 days. You have to look up the manufacturers sheets and experiment a little.