Starting New, Doing it Right!

[timvz]

Pressure of a column of water is .434 psi per foot (on the planet earth). So, at three feet you have 1.3 psi. Sheer and tensile strength of construction glue should be plenty strong for that.
Did you glue the blocks to the floor and glue them end-to-end?

 

[Jason]

I thought water (Pure Water) was .44psi per foot of depth? The Glue I am using is 400psi holding strength so I would think it would be ok?
Thanks for the Explanation Catfishnut, but I am trying to be revolutionary here LOL. If it does not hold then I will be fully expecting a lashing from this community and will never underestimate water pressure again. I have asked 8-10 Contractors, friends, family and even Culligan Water individuals who all said it should be ok, One guy said he built a 10' high rain water reservoir stacked with the thinner 6x8x16 cinder blocks using the same stuff I used and he said it has held for 5 years so far?

 

[timvz]

Salt water is .44, I think. Note, it isn't just a simple comparison of 1.3 psi to 400 psi. You've got to account for how much surface area with water pushing and how much glue holding it in. I think you'll be ok unless you've been really skimpy with the amount of glue.

 

[timvz]

Let me be clear that I'm very bored at the moment. I calculated the total force (hopefully correctly) on a 3ft x 6ft wall to be 1687 lbs by integrating over the total surface area. So, you'll need 1687/400 sq inches of total glue, or about 4 square inches. ...assuming that 400 is the proper number for your application.

 

[Catfishnut]

What!? Atmospheric pressure? The atmosphere presses on both sides of the wall and cancels out. Only thing they need to worry about is a 2 or 3 foot column of water. Could still be significant, but probably not.

Timvz,

I agree, but that would be true when there is air on both sides of the wall. When you have water on one side, the atmospheric pressure pushes down on the surface of the water and since water cannot be compressed, that force is amplified outwards like a hydraulic piston. That force is additive to the pressure of the mass of the water alone. The air around the outside of the wall can be compressed and therefore it offers little combative resistance against the forces from inside.

Gordy

 

[Jason]

you guys have me scared lol, I filled with water last night about 6-8" shy of topping it off when a voice told me to fill the blocks! ok, so even though this badboy is holding fine, i need to stick to the title of fthis thread. now would pvc with sand be ok, or mixed quick crete down the hatches be better?

 

[sissy]

wet sand maybe packed in but if it looks ok ,then you maybe worrying for nothing .Geeze enjoy your new house with your new wife .My block just sitting on clay have not moved out in 11 years .I packed wet clay in each hole .No stuff out side the block to hold them in place and water goes up to the block

 

[sissy]

granted it is only 1 row but they were as level as the day I put them in and just as solid .I did add a little more of my clay soil .You could fill them with wet sand ,down pressure verses out pressure .The shear weight should hold them in place ,stop fretting ,you will give your self an ulcer over a pond .

 

[Catfishnut]

you guys have me scared lol, I filled with water last night about 6-8" shy of topping it off when a voice told me to fill the blocks! ok, so even though this badboy is holding fine, i need to stick to the title of fthis thread. now would pvc with sand be ok, or mixed quick crete down the hatches be better?

Jason,

The block adhesive you used might just be fine all alone since the walls are not too high, but I would hate to see it fail sometime down the road. It is up to you to decide how confident you are with the adhesive.

I personally would fill every other block hole with pre-mixed quickcrete and fill the ones in-between with sand. The quickcrete would mechanically bond each section to the other and then you will never have to worry at all.

Gordy

 

[Jason]

Thanks again guys and gals, I have bought (6) 1"x5' PVC Pipes, (3) 25lb bags of Special Kitty litter, 2 scoops of Fill Dirt for tomorrow's fill. I am going to mix the clay litter with the fill dirt and run every other hole with a 20" PVC pipe and fill in the dirt and litter mix around and inside it, then wet it down to clump and stick better. This should hopefully work just fine, will keep you posted.

 

[timvz]

Timvz,

I agree, but that would be true when there is air on both sides of the wall. When you have water on one side, the atmospheric pressure pushes down on the surface of the water and since water cannot be compressed, that force is amplified outwards like a hydraulic piston. That force is additive to the pressure of the mass of the water alone. The air around the outside of the wall can be compressed and therefore it offers little combative resistance against the forces from inside.

Gordy

Gordy,

I don't mean to distract this thread with a separate discussion, but I have to respectfully disagree with you. Incompressible fluids go up in pressure very quickly if you are talking about something like an actual piston that moves a prescribed distance. Imagine pushing down on a fluid filled piston verses an air filled one. The fluid filled piston is going to increase in pressure exponentially faster. But this isn't what the atmosphere does. It has 14.7 psi to push down with. That is all. Doesn't matter if it's pushing on water, air, or the plants in your pond. 14.7 is all you get (at the surface of the pond). Granted pressure rises faster as you go down deeper through the water, but that's because water has more mass than air. You're right about a piston, and you can actually think about air pressure as a column of air (piston) above the pond, but it doesn't really behave like a piston that is being compressed a prescribed distance (like in some engineering problem). The piston is really only going to move as far as the force behind it is capable of moving it, though. Ok, sorry for the distraction from your primary subject, Jason.

Tim

 

[Jason]

Ok, So I filled the Cinder block walls with fill sand this weekend and drove 23" x 1" PVC down every other hole then wet the sand and packed it down each hole until solid. I filled up the rest of the pond after and has been good to go since Saturday morning. I started putting the water fall on top but after test running it, the Cinder block and square pavers like to absorb water and drip off the back of the pond?

Today at lunch I am bring over two 12x24" aluminum sheets that will sit un-level with the pond and will be under the water fall so the water that drips will be ran back into the pond. I have the pumps running and UV light on as well as filter hooked up. I added conditioner and left algae on liner and pumps to get it started. If my water checks out I will have the fish in there maybe tonight...

 

[Jason]

here are a couple of pics of the spillways in action

 

[sissy]

Are you going to stain the block with concrete stain or leave it natural .If you don't have your corner blocks glued you can hide your cords under them .Which side are you putting your filter block on ,is it the wall you have them on .Could imagine something like that as a coffee table or a table to eat at .great job

 

[Jason]

I am thinking about staining the Cinder blocks Sissy, just not sure what color yet? The Flat pavers on top are not going to be glued down and I will be hiding the pump cords under the corners like you mentioned (We think alike!). The Filter is not going to be in the pond as shown just that it is leaking right now but is supposed to be in-between the house exterior wall and pond wall hidden when finished. I was thinking the same thing on the edge of the pond put some chairs or a bench so you could sit at, but someone would probably spill something in the pond if I did that and kill the fish lol