ok, the tank is 30years old... and located in Canary Island, probably they considered the seismic loading. On the side of safety is best done as was done.
Hi, i have that change a bottom of tank. The existing tank have a annular bottom plate with the same thickness than the bottom tank thickness, it is 1/4in. The dimension of the tank are: diam 18ft and 24ft of high.
i shall have use the annular bottom plates? or how the tank had been made of...