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In this paper, performance criteria for the seismic design of industrial liquid storage tanks and piping systems are proposed, aimed at introducing those industrial components into a performance-based design (PBD) framework. Considering “loss of containment” as the ultimate damage state, the proposed limit states are quantified in terms of local quantities obtained from a simple and efficient earthquake analysis. Liquid storage tanks and the corresponding principal failure modes (elephant's foot buckling, roof damage, base plate failure, anchorage failure, and nozzle damage) are examined first. Subsequently, limit states for piping systems are presented in terms of local strain at specific piping components (elbows, Tees, and nozzles) against ultimate strain capacity (tensile and compressive) and low-cycle fatigue. Modeling issues for liquid storage tanks and piping systems are also discussed, compared successfully with available experimental data, and simple and efficient analysis tools are proposed, toward reliable estimates of local strain demand. Using the above reliable numerical models, the proposed damage states are examined in two case studies: (a) a liquid storage tank and (b) a piping system, both located in areas of high seismicity.

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The present paper investigates sloshing effects on the earthquake design of horizontal-cylindrical and spherical industrial vessels. Assuming small-amplitude free-surface elevation, a linearized sloshing problem is obtained, and its solution provides sloshing frequencies, modes, and masses. Based on an “impulsive-convective” decomposition of the container-fluid motion, an efficient methodology is proposed for the calculation of seismic force. The methodology gives rise to appropriate spring-mass mechanical models, which represent sloshing effects on the container-fluid system in an elegant and simple manner. Special issues, such as the deformability of horizontal-cylindrical containers or the flexibility of spherical vessel supports, are also taken into account. The proposed methodology can be used to calculate the seismic force, in the framework of liquid container earthquake design, and extends the current design practice for vertical cylindrical tanks stated in existing seismic design specifications (e.g., API Standard 650 and Eurocode 8). The methodology is illustrated in three design examples.

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