Force on sides of a pool I am going to create a large pool of water for a stage production. The volume of water will be 6m x 5.2m x .15m deep. I want to check how much pressure or force will be exerted on the surrounding wooden frame, so I can check the tensile strength of the wood is sufficiently capable of holding the water. I would appreciate assistance on what calculations I need to make?
Many thanks.
 A: i'm gonna try here, but i'm kinda short of information; such as how much free space do you have surrounding the pool and how thick is the wood on the perimeter.  i'm american, so bear with me, i think in SAE terms.
your answer is not very much.  each cm of length will have 120 grams of pressure exerted upon it.  so each meter will have 12000 grams or 12kg.
this is similar to forming concrete slabs. assuming that the perimeter wood is 1 1/2" (4cm) you will need 2 triangular braces per meter and 1 brace at each corner.  (45+45+90=180 degrees)  Make the braces equal (.15m) on 2 sides and cut the angled (45 degrees) to fit (21.2cm over all length)(consider that the vertical and horizantal piece will occupy some of this space, so it will be shorter.) 
lastly, how will you seal the water in?  if you use a plastic liner, it would be best.  if you just caulk the joints, the entire form will want to float.  wood does float on water.  just to be safe, attach braces to the form and to the floor with screws.  
if you have more questions, just mail me
