[mande78717]

I am in the process of installing a patio with concrete pavers. I have dug out my area, and filled it partially with crush and run. After running a plate tamper over the area, I have found that there are soft spots. The spots seem to be damp, in fact, one of them is the consistency of freshly mixed concrete. I tried tamping the areas even more and adding more crush and run, but they are still soft.

Does the crush and run set up like concrete? I am waiting overnight and hoping this is the case.

 

[Willie T]

You don't happen to live in Georgia, do you?

 

[Daniel Holzman]

First of all, what exactly is crush and run, never heard the term. Second, how many inches of crush and run did you put down, and what was under it?

 

[concretemasonry]

You did not dig deep enough to remove the poor subbase or to get enough depth on compacted base to span the poor subbase (fill or bad natural soil).

Your base (whatever you call it) is the same stuff used under an asphalt or concrete surface. The setting base over the compacted base should be 1" of UNCOMPACTED concrete sand, so the compacted base should be graded to be parallel to the finished paver surface after vibration the fine sand into the joints and drawing up the concrete sand. This will maintain a uniform setting bed thickness and provide and even finished surface. Any provisions for drainage should be taken care of by the slope (if any) required for drainage and not by adjusting the setting bed thickness.

You may get away with less control for a pation than you need for a driveway, street, airport taxiway or a 40 acre ship unfloading port served by straddle loaders.

Dick

 

[mande78717]

I live in South Carolina. Crush and run is gravel (I believe limestone) used as a base for patios, sidewalks, driveways, etc.

The problem I am having is that I have water seeping into the base from two spots at the edges. I believe this is due to the fact that we have had a lot of rain over the past few weeks and the ground surrounding the patio has not completely drained.

I have excavated down a couple of inches and tamped it down some more. Hopefully, it will dry out. Although the areas are still a little softer than I would like (I want it to be as hard as concrete before I lay my sand out), the areas have seemed to have gotten a little stiffer over night.

If I go ahead and lay the sand and the pavers out before the base is completely dry and hard, will it continue to dry?

 

[jomama45]

The water entering the excavated area is definately the problem. Either find a way to dam it off, or wait until it dries up. Generally, if we hit large areas of wet subsoil, we leave for a few days to allow it to dry on it's own. Small areas of "mushy" gravel we dig out by hand (including any soft soil) & replace with dry gravel. Don't cover the wet gravel base, it's not worth it to save a few days time.

 

[concretemasonry]

mande -

If you have a bad sbbase or base that is too wet, you will not be able to compact it no matter how hard you beat on it.

When it get drier, it will shrink a bit and cause settlement where it was too wet.

 

[Scuba_Dave]

why did you come to that conclusion?

Why do you still have that red X ??

 

[mande78717]

Thanks for the help. I am going to let it dry for a few another day or two. I have some extra gravel that I can fill in when it shrinks from drying. It already seems to be drying out - the soft areas are beginning to harden.