Estimating eepage through cracked concrete

[cel66]

I want to estimate the flow of water through cracks in the bottom of concrete lined pond. Givens: water depth 9ft, concrete thickness 5 inches, foundation bedding is 5 inches sand, average crack width 1mm (0.0394 in), crack length 100ft. Any suggestions on the best equations to use would be appreciated.

Thanks!

 

[bimr]

The WAG equation would be as good as any other.

You will be better served if you did a simple mass balance on the pond.

 

[Ron]

Agree with bimr....the classical equations don't apply because the conditions are not the same. Depending on the amount of head, you might never reach a steady-state flow condition.

In concrete, cracks are usually wider at the top than the bottom, but since you have a submerged condition, it might be the reverse...but you don't know that, most likely.

 

[cvg]

hard to tell if the crack is the controlling factor or if subsurface flow through the sand and into the ground (using Darcy's Law) might also control. Would need a lot more data to even make a SWAG