pressure relieve valves

huangyhg

pressure relieve valves
how can existence of pressure relieve valves in floor of underground concrete tank be taken into account  to lessen  influence of high water table on walls of a tank? should walls be designed for hydrostatic pressure of max wt anyway?
suggest that you ignore the valves and design the wall for the full load. no mechanical device is perfect - when the day comes that the valves fail, you do not want to risk wall failure also. chances are that the differential construction cost for "stronger" walls is minor anyway.
it's the net pressure that triggers design for strength and deformation compatibility.
during the service life of the tank, are there events in which the tank is empty?
and at the same time subject to atmospheric pressure?
how about events where the tank is full, then pressurized while the water table outside is drawn down?