I live just outside Dallas. I have expansive clay. In the back we constructed a pond. It's about 3 feet deep and 5 feet side to side. I want to fill it in and thinking of using concrete sand. Once it is filled we will cover it with flag stone to match the rest of that area. Is fill sand OK for this purpose?
3:23p, 4/12/24
I don't see what it would hurt if you plan on covering with flagstone. Sand should reduce any issues with settling over time if you were to fill with dirt.
4:41p, 4/12/24
That sand & its price is tempting all righty ...
The potential issues will always be surface cracks where the fill below supporting has different forces from the existing grade supporting flagstone esp. when both get wet.
A structural engineer might get involved here, might suggest you begin with pushing "cut&fill" soils into hole from as far out as flagstone perimeter + a few feet
THEN bringing in #1 Select Fill for compaction in 6-inch lifts w/sheepsfoot (or dozer + time to settle) to 90% Proctor.
Then begins the advice on what to do next to support forever the flagstone, if not reif.conc flatwork.
The potential issues will always be surface cracks where the fill below supporting has different forces from the existing grade supporting flagstone esp. when both get wet.
A structural engineer might get involved here, might suggest you begin with pushing "cut&fill" soils into hole from as far out as flagstone perimeter + a few feet
THEN bringing in #1 Select Fill for compaction in 6-inch lifts w/sheepsfoot (or dozer + time to settle) to 90% Proctor.
Then begins the advice on what to do next to support forever the flagstone, if not reif.conc flatwork.
5:27p, 4/12/24
I just fill in between stones with crushed granite. I don't know about compaction. I thought I would just soak it really well before putting the flag stones on top.
12:05a, 5/2/24
Good advice from tgivaughn.
If you want to get crazy you could mix in a few bags of Portland cement with the Concrete sand to make your own light cement stabilized blend.
If you want to get crazy you could mix in a few bags of Portland cement with the Concrete sand to make your own light cement stabilized blend.
Thanks & Gig 'Em
10:19a, 5/2/24
In reply to tgivaughn
Unless I'm misunderstanding his size descriptions, this is just a tad bit overkill for a 25 SF area.tgivaughn said:
A structural engineer might get involved here, might suggest you begin with pushing "cut&fill" soils into hole from as far out as flagstone perimeter + a few feet
THEN bringing in #1 Select Fill for compaction in 6-inch lifts w/sheepsfoot (or dozer + time to settle) to 90% Proctor.
11:37a, 5/2/24
In reply to YellAg2004
I don't know, when I read 5x5 pond, I immediately thought I better call a structural engineer, get a soils report, and get the D6 out here.YellAg2004 said:Unless I'm misunderstanding his size descriptions, this is just a tad bit overkill for a 25 SF area.tgivaughn said:
A structural engineer might get involved here, might suggest you begin with pushing "cut&fill" soils into hole from as far out as flagstone perimeter + a few feet
THEN bringing in #1 Select Fill for compaction in 6-inch lifts w/sheepsfoot (or dozer + time to settle) to 90% Proctor.