force on a dam

Ask a question or request a feature related to the website or forum...

Moderator: scott

Post Reply
bilbo
Dabbler
Dabbler
Posts: 24
Joined: Fri Oct 19, 2012 5:33 pm
Location: Scotland

force on a dam

Post by bilbo »

Just a quick question- does the force acting on a dam from the water depend only on the vertical area of water and the depth of the water or is it also dependant on the volume of water as well?

I would have thought that the greater the volume of the water, the greater the force on the dam.
User avatar
Fletcher
Addict
Addict
Posts: 8200
Joined: Wed Nov 05, 2003 9:03 am
Location: NZ

re: force on a dam

Post by Fletcher »

Volume has no effect on the forces - only height [depth] is important, & to remember that Thrust [force] = Pressure x Area & therefore P = F/A.

Try asking My Google about ...

Pascal's Law

Hydrostatic Pressure on dam walls

http://www.math.ucsb.edu/ugrad/fluid.pdf
rlortie
Addict
Addict
Posts: 8475
Joined: Thu Jan 06, 2005 6:20 pm
Location: Stanfield Or.

re: force on a dam

Post by rlortie »

Thank you Fletcher for not only explaining but for the posted link.

Having spent 20+ years in the hydroelectric profession I of course agree. Your link only adds another clip of ammo when I am ready to confront Jim_Mich regarding 3rd dimensional weights adding force to a wheel.

Ralph
bilbo
Dabbler
Dabbler
Posts: 24
Joined: Fri Oct 19, 2012 5:33 pm
Location: Scotland

re: force on a dam

Post by bilbo »

Thank you Fletcher- your post is greatly appreciated.
I remember doing fluid dynamics a long time ago and your link will help me refresh my memory.
User avatar
daxwc
Addict
Addict
Posts: 6700
Joined: Tue Mar 27, 2007 3:35 am

re: force on a dam

Post by daxwc »

Ralph:
Your link only adds another clip of ammo when I am ready to confront Jim_Mich regarding 3rd dimensional weights adding force to a wheel.
Interesting statement though adding force or stress is not always adding movement.

Example: compress a gas beyond the structures limit it will blow up. Compress a fluid against a structure limit it will just crack. But the energy you add into both are also very different.
What goes around, comes around.
rlortie
Addict
Addict
Posts: 8475
Joined: Thu Jan 06, 2005 6:20 pm
Location: Stanfield Or.

re: force on a dam

Post by rlortie »

Dax,

The only force I refer to is mass and the gravitational Pe of said mass. No stress implied as one cannot compress a liquid, it does however expand and contract with temperature changing density or weight per unit.

No energy added other than gravity and quantity of mass per cubic inch or cubic feet depending on size of containment.

Ralph
Post Reply