Application of base isolation systems in seismic design of steel water storage tanks

Reference number for ethics: 2023FEBEFREC-STD-048<br>This study examines the seismic behaviour of a modular steel water storage tank equipped with a base isolation system, focusing on the friction pendulum system (FPS) as the primary isolation mechanism. Analytical models were developed using the lumped mass analogy technique, where the masses are referred to as convective, impulsive, and base masses. Numerical simulations were performed using Abaqus software, considering fluid-structure interaction, to simulate the dynamic behaviour of an isolated tank under seismic excitation. A comparative analysis was undertaken between isolated and non-isolated tanks and those incorporating an FPS to assess the system’s efficiency. Moreover, the study was conducted to measure the effects of key system parameters on the base isolation of liquid storage tanks. Key parameters considered in this study include the tank’s aspect ratio, isolation period, and friction coefficient. The objective was to assess the performance of a tank supported by friction pendulum bearings (FPS). The application of base isolation in steel water storage tanks can produce different results, influenced by factors such as isolation system design, tank properties, seismic intensity, and overall structural stability. To achieve the desired results, conducting a comprehensive engineering analysis and considering design elements were crucial. The approach involved the application of simulation-based analysis to investigate how base isolation affected the seismic response of tanks during an earthquake. The research established the efficiency of the isolation system in alleviating fluid-induced forces by attaining potential stability, less hydrodynamic pressure, wall buckling risk reduction, better control of water behaviour, decrease and stable bearing shear impact in isolated tanks compared to non-isolated tanks.

伦理审查编号：2023FEBEFREC-STD-048
本研究针对配备基础隔震系统的模块化钢制储水罐的抗震性能展开研究，以摩擦摆系统（Friction Pendulum System, FPS）作为核心隔震机制。研究采用集中质量类比法构建分析模型，将模型质量划分为对流质量、冲量质量与基础质量三类。本研究借助Abaqus软件开展数值模拟，考虑流固耦合效应，以模拟隔震储罐在地震激励下的动力响应。研究开展了隔震储罐、非隔震储罐及采用FPS的储罐的对比分析，以评估该隔震系统的实际效能。此外，本研究旨在量化关键系统参数对储液罐基础隔震效果的影响，本次考量的关键参数包括储罐径高比、隔震周期与摩擦系数。本研究的核心目标为评估采用摩擦摆支座（FPS）支撑的储罐的抗震性能。基础隔震技术在钢制储水罐中的应用效果会因隔震系统设计方案、储罐自身属性、地震烈度及整体结构稳定性等多重因素产生差异。为达成预期研究与应用目标，开展全面的工程分析并兼顾各类设计要素至关重要。本次研究采用基于模拟的分析方法，探究基础隔震对地震作用下储罐抗震响应的影响规律。本研究证实，相较于非隔震储罐，该隔震系统可通过提升结构整体稳定性、降低流体动压力、削弱罐壁屈曲风险、更好地管控水体运动、减少支座剪力并使隔震储罐的支座剪力更趋平稳，从而有效缓解流体诱导荷载，显著提升系统整体效能。