Performance limits of base-isolated liquid storage tanks with/without supplemental dampers under near-fault earthquakes

Liquid-filled tanks are effective storage infrastructure for water, oil, and liquefied natural gas (LNG). Many such large-scale tanks are located in regions with high seismicity. Therefore, very frequently base isolation technology has to be adopted to reduce the dynamic distress of storage tanks, preventing the structure from typical modes of failure, such as elephant-foot buckling, diamond-shaped buckling, and roof damage caused by liquid sloshing. The cost-effective seismic design of base-isolated liquid storage tanks can be achieved by adopting performance-based design (PBD) principles. In this work, the focus is given on sliding-based systems, namely, single friction pendulum bearings (SFPBs), triple friction pendulum bearings (TFPBs), and mainly on the recently developed quintuple friction pendulum bearings (QFPBs). More specifically, the study is focused on the fragility analysis of tanks isolated by sliding-bearings, emphasizing on isolators’ displacements due to near-fault earthquakes. In addition, a surrogate model has been developed for simulating the dynamic response of the superstructure (tank and liquid content) to achieve an optimal balance between computational efficiency and accuracy.

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A Study on the Sloshing Problem of Vertical Storage Tanks under the Action of Near-Fault Earthquakes

Advances in Civil Engineering ◽

10.1155/2020/1097696 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Lijian Zhou ◽

Tian Xu ◽

Zhaohong Lu ◽

Dong Zhang

Keyword(s):

Wave Height ◽

Storage Tank ◽

Small Sample Size ◽

Ground Motions ◽

Reference Value ◽

Small Sample ◽

Storage Tanks ◽

Near Fault ◽

Practical Engineering ◽

Near Fault Earthquakes

In this study, through a vibration table test, finite element simulation, and research on the rationality of the wave-height fortification of national storage tank specifications, the sloshing response of vertical storage tanks under the action of near-fault ground motion was analyzed. The test results showed that the sloshing wave height of a vertical storage tank was larger under near-fault or long-period ground motions, and the relationship between the sloshing wave height and the peak acceleration of input ground motions was approximately linear. The numerical simulations of the model tank showed that the simulation wave height and the test wave-height data were well fitted. Therefore, it was feasible to simulate the sloshing of large vertical storage tanks using ADINA software. In addition, a large number of sloshing simulations of near-fault ground motions on 10,000 m3 vertical storage tanks were performed. The simulated wave height had a high correlation with the predominant period or pulse period of near-fault ground motions. Under the calculation with similar parameters, the wave height of the tank standard in several countries had a lower fortification of the near-fault excitation wave height. Through the root mean-square method using a small sample size, a wave-height correction under a near-fault effect was applied to the wave-height formula for the Chinese tank seismic specification. Finally, the problem of a double-damping correction was addressed by adjusting China’s GB50341 wave-height formula. This work provides a reference value for practical engineering applications.

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Behavior of base-isolated liquid storage tanks under synthetic near-fault earthquake pulses

Life-Cycle of Engineering Systems ◽

10.1201/9781315375175-356 ◽

2016 ◽

Cited By ~ 1

Author(s):

C Alhan ◽

E Güler ◽

H Gazi

Keyword(s):

Storage Tanks ◽

Near Fault ◽

Liquid Storage

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Parametric study of stochastic seismic responses of base-isolated liquid storage tanks under near-fault and far-fault ground motions

Journal of Vibration and Control ◽

10.1177/1077546316647576 ◽

2016 ◽

Vol 24 (24) ◽

pp. 5747-5764 ◽

Cited By ~ 1

Author(s):

Sina Safari ◽

Reza Tarinejad

Keyword(s):

Base Isolation ◽

Seismic Analysis ◽

Ground Motions ◽

Characteristic Parameter ◽

Statistical Linearization ◽

Storage Tanks ◽

Earthquake Excitation ◽

Isolation System ◽

Near Fault ◽

Liquid Storage

Seismic response of base isolated steel liquid storage tanks is investigated in this study by a stochastic approach in frequency domain. For the purpose of evaluating different frequency contents of seismic events on the responses of fixed and isolated tanks, the earthquake excitation is characterized by power spectral density function. Since earthquake is a random process, stochastic seismic analysis is used and root mean square response predicts behavior of system properly. Two types of isolation system are assumed and nonlinear behavior of base isolation systems are developed by an iterative statistical linearization scheme. The study demonstrates the influence of each characteristic parameter of the storage tanks and isolation system and also excitation features. It is confirmed that near-fault earthquake excitations amplify the overall response of the system. Base isolation is known as an effective technique to reduce responses appropriately. It is demonstrated that the sloshing responses of the tanks is significantly reduced by sliding bearing. Further, excitation parameters, PGV/PGA ratio of records and pulse period in near-fault ground motions, that represent differences in two sets of earthquakes are defined to recognize variation of responses.

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