The comparison of DYNA3D to approximate solutions for a partially- full waste storage tank subjected to seismic loading

Evaluating the dynamic response of large, aboveground storage tanks exposed to seismic loading is multifaceted. There are foundation-structure and fluid-structure interaction effects that can influence the overall tank behavior and likely failure modes. Additionally, local stresses at anchor bolt support chair attachments and the shell-to-floor junction can be difficult to quantify without detailed finite element analysis (FEA). Often times, performing explicit dynamic analysis with liquid sloshing effects can be time consuming, expensive, and even impractical. The intent of this paper is to summarize simplified analysis techniques that can be leveraged to evaluate aboveground storage tanks subject to seismic loading. Closed-form calculations to establish a recommended design for a tank, including seismic considerations, are available in storage tank design standards, including API 650 [1] (Appendix E). Seismic design standards have evolved significantly in recent years. Furthermore, for many vintage, in-service storage tanks, explicit seismic considerations were not incorporated into the original design. In Part I of this study, these design equations and other closed-form solutions are used to evaluate the structural integrity of a large, in-service, mechanically-anchored storage tank. The design equations in API 650 [1] are used to form the basis of simplified, equivalent static analysis, where seismic loads are applied to a three-dimensional FEA model via equivalent lateral body forces. These practical results are then compared to explicit dynamic seismic behavior of the same tank with fluid-structure interaction effects considered (in Part II of this study [2]). These comparisons offer insight into the appropriateness of using simplified hand-calculations and equivalent static analysis (and their relative conservatism) in lieu of more rigorous explicit dynamic and fluid sloshing simulations.

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Apparatus for providing a controlled flow of waste material from a waste storage tank

Environment International ◽

10.1016/0160-4120(94)90291-7 ◽

1994 ◽

Vol 20 (4) ◽

pp. XV

Keyword(s):

Storage Tank ◽

Waste Material ◽

Waste Storage ◽

Controlled Flow

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AP1000 Shield Building Dynamic Response for Different Water Levels of PCCWST Subjected to Seismic Loading considering FSI

Science and Technology of Nuclear Installations ◽

10.1155/2015/840507 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Daogang Lu ◽

Yu Liu ◽

Xiaojia Zeng

Keyword(s):

Storage Tank ◽

Seismic Analysis ◽

Cooling System ◽

Water Storage ◽

Seismic Loading ◽

Water Levels ◽

Von Mises Stress ◽

Fe Model ◽

Water Storage Tank ◽

Von Mises

Huge water storage tank on the top of many buildings may affect the safety of the structure caused by fluid-structure interaction (FSI) under the earthquake. AP1000 passive containment cooling system water storage tank (PCCWST) placed at the top of shield building is a key component to ensure the safety of nuclear facilities. Under seismic loading, water will impact the wall of PCCWST, which may pose a threat to the integrity of the shield building. In the present study, an FE model of AP1000 shield building is built for the modal and transient seismic analysis considering the FSI. Six different water levels in PCCWST were discussed by comparing the modal frequency, seismic acceleration response, and von Mises stress distribution. The results show the maximum von Mises stress emerges at the joint of shield building roof and water around the air inlet. However, the maximum von Mises stress is below the yield strength of reinforced concrete. The results may provide a reference for design of the AP1000 and CAP1400 in the future.

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