By separating these masses, ACI 350.3-06 allows engineers to calculate the natural periods of vibration for both the tank structure and the liquid contents, which is essential for determining the appropriate seismic response coefficients from spectral acceleration maps.
The use of ACI 350.3-06 provides several benefits, including:
If you are using this for a current project, verify whether ACI has superseded it with a newer version (e.g., ACI 350.3-20 or a revision). The 2006 edition may still be permitted by reference in some older specifications, but many engineers today rely on ACI 350’s durability chapters or alternative guides (e.g., from WEF or ASCE).