Aci-350.3-06.pdf
Rectangular tanks on grade must be checked for uplift and sliding. Circular tanks—often prestressed—require special anchorage design. The -06 edition provides load combinations specific to concrete tanks, which differ from ASCE 7 because they include the fluid self-weight as a variable load, not a dead load.
The code applies to rectangular and circular concrete tanks, reservoirs, and basins. It explicitly covers structures containing liquids with mass density up to 75 lb/ft³ (similar to water). Importantly, it excludes pressure vessels and buried tanks where soil provides restraint.
To understand ACI-350.3-06, one must first understand the "ACI 350" family. While ACI 318 controls general building construction, ACI 350 governs Environmental Engineering Concrete Structures. These include structures that handle liquids with high potential for environmental damage if leaked—specifically potable water, sewage, and industrial chemicals.
ACI 350 splits into several parts:
The ".3" identifier is crucial. It deals exclusively with earthquake loading. The "-06" suffix indicates the 2006 edition of the standard.
The PDF details how to compute the pressure distribution on walls and the base shear. A key formula from Section 4.3.1 is:
[ P_i = C_i \cdot (W_i) \cdot (S_DS) ]
Where (P_i) is impulsive force, (W_i) is impulsive liquid weight, and (S_DS) is the short-period spectral acceleration from the site geology. The convective force uses (S_D1) (1-second period) instead.
ACI 350.3-06 requires the designer to choose a structural system similar to those used in buildings but adapted for tanks:
The standard outlines a step-by-step procedure for analyzing tanks (typically ground-supported rectangular or circular tanks): ACI-350.3-06.pdf
ACI 350.3-06 provides specific requirements for the earthquake-resistant design of concrete liquid-containing structures. While general building seismic codes (like ASCE 7 or the International Building Code) focus on occupant safety, ACI 350.3 focuses on containment.
Key Objectives:
Seismic Analysis of a Rectangular Liquid-Containing Tank Using ACI 350.3-06: A Case Study Rectangular tanks on grade must be checked for