Hydrodynamic force on internal walls for global stability
Hydrodynamic force on internal walls for global stability
(OP)
I am designing de-silting chamber. There are two divide walls in the chamber, making three bays, independent of each other. I want to evaluate the factor of safety against sliding for the chamber. The critical case is the tank full of water and earthquake. The question is that, to determine the total sliding force, should the hydrodynamic force be considered on exterior wall and the two interior walls?






RE: Hydrodynamic force on internal walls for global stability
The other option is to determine the total base shear considering the total impulsive force of water in the tank.
Which option should be adopted for the design?
RE: Hydrodynamic force on internal walls for global stability
However, due to friction resistance, the worst sliding case may not actually be the maximum load case. You'll need to consider all possible tank fill configurations, and the force and sliding resistance for each of them.
Brian C Potter, PE
http://simplesupports.wordpress.com
RE: Hydrodynamic force on internal walls for global stability
One more question. If I consider the entire water volume as "impulsive mass" (without considering convective mass), and simply determine the "base shear" = total weight x OBE (0.24g). Is this be the same as if using the westergaard hydrodynamic pressure to determine the base shear.
Let me put this question in another way. Consider a water tank with no internal walls. The hydrodynamic force will be acting on one wall. We also calculate the base shear considering complete weight of water in the tank. No if the same tank is divided into three part (two internal walls), the hydrodynamic force will act on three walls (3 times than for the tank without internal walls). While the base shear considering the weight of water in the tank remains the same.
One additional question. Should we use the Wastergaard formula for hydrodynamic force or the 350.3 for the seismic analysis of tank?
RE: Hydrodynamic force on internal walls for global stability
I'm unfamiliar with the westergaard method. I've always designed using the method spelled out in ACI 350.3.
Brian C Potter, PE
http://simplesupports.wordpress.com