Optimal design based on analytical solution for storage tank with inerter isolation system

Struct Control Health Monit

Pan

et al. 2020

Self Cite

101

Summary Interactions among an inerter, spring, and energy dissipation element (EDE) in an inerter system can result in a higher energy dissipation efficiency compared to a single identical EDE, which is referred to as the damping enhancement effect. Previous studies have mainly concentrated on the vibration mitigation effect of the inerter system without an explicit consideration or utilization of the damping enhancement mechanism. In this study, the theoretical essence of the damping enhancement effect is discovered, and a universal design principle is proposed for an inerter system. A fundamental equation is found and demonstrated on the basis of closed‐form stochastic responses, which establishes a bridge between the damping deformation enhancement factor (DDEF) and the response mitigation ratio, thus clarifying the relationship of the damping enhancement effect and the response mitigation effect. Inspired by the equation, a novel damping‐enhancement‐based strategy is proposed to determine the key parameters of an inerter system. Following the performance‐demand‐based design philosophy, the parameters of the inerter system can be determined in the design condition of a target‐damping‐enhancement effect. Through the implementation of the damping enhancement equation, the damping parameter of an inerter system can be directly obtained by the prespecified DDEF and the displacement response mitigation ratio. The influence of parameters on the response mitigation effect and the damping enhancement effect is then investigated to determine ways of obtaining the other two parameters in an inerter system. Finally, design examples are conducted to verify the proposed strategy and the theoretical relationship revealed by the damping enhancement equation. The results show that the proposed design strategy explicitly utilizes the damping enhancement effect for vibration control, where the target of the DDEF is effective in enhancing the efficiency of the EDE for energy dissipation. In the design condition of the target DDEF, the implementation of the proposed damping enhancement equation provides an inerter system with a practical equation to determine the key parameters of an inerter system in a direct manner.

Section: Introductionmentioning

confidence: 99%

Damping enhancement principle of inerter system

Zhang

Struct Control Health Monit

Pan

et al. 2020

Self Cite

101

“…To predict the parameters of the base isolation system, they proposed a regression equation that was calibrated against a set of optimally designed baseisolated systems using a genetic algorithm. Jiang et al [8] proposed an optimal design method based on an analytical solution for a storage tank with an inerter isolation system. Nevertheless, the aforementioned studies modeled a building as a shear-type structure with one lateral degree of freedom at each story.…”

Section: Introductionmentioning

confidence: 99%

Two‐Stage Optimization Method for the Bearing Layout of Isolated Structure

Advances in Civil Engineering

Tian

et al. 2021

Design of seismic isolated building is often a highly iterative and tedious process due to the nonlinear behavior of the system, a large range of design parameters, and uncertainty of ground motions. It is needed to consider a comprehensive optimization procedure in the design of isolated buildings with optimized performances. This can be accomplished by applying a rigorous optimization technique. However, due to many factors affecting the performance of isolated buildings, possible solutions are abundant, and the optimal solution is difficult to obtain. In order to simplify the optimization process, an isolated building is always modeled as a shear-type structure supported on the isolated layer, and the optimal results are the parameters of the isolated layer which could not be used as a practical design of the isolated structure. A two-stage optimization method for designing isolated buildings as a practical and efficient guide is developed. In the first stage, a 3D isolated building model is adopted that takes into account of nonlinear behavior in building and isolation devices. The isolation devices are simplified as a kind of lead-rubber bearing. The genetic algorithm is used to find the optimal parameters of the isolated layer. In the second stage, the location parameters of isolation bearing layout are optimized. Moreover, the cost of the isolation bearing layout should be as low as possible. An integer programming method is adopted to optimize the number of each type of isolator. Considering vertical bearing capacity of isolators and the minimum eccentricity ratio of the isolated layer, the optimal bearing layout of the isolated building can be obtained. The proposed method is demonstrated in a typical isolated building in China. The optimum bearing layout of the isolated building effectively suppresses the structural seismic responses, but the cost of the isolated layer might slightly increase.

“…The inerter‐based system is widely accepted and effective for vibration control 1,2 and has attracted many researchers working on the relevant invention of devices 3–7 and optimal designs 8–11 . In recent literature, the performance evaluation and benefits of inerter‐based systems for the protection of building structures, 12–18 wind turbine towers, 19 storage tanks, 20 and semi‐submersible platforms, 21 the vibration suppression of cables 22 and machines, 23 and the wind‐induced vibration mitigation of tall buildings 24,25 have been examined. The ideal linear inerter is a massless two‐terminal inertia element that can produce an inertia force F I in the form of

F_{I} = m_{in} {\ddot{u}}_{r}

, 26 where

{\ddot{u}}_{r}

represents the relative acceleration across the two terminals of the inerter, and m in is called the inertance.…”

Section: Introductionmentioning

confidence: 99%

Input energy reduction principle of structures with generic tuned mass damper inerter

Struct Control Health Monit

Zhang

Pan

et al. 2020

Self Cite

The incorporation of the inerter with tuned mass damper yields the inerterbased tuned mass damper that has been verified as effective lightweight or performance-enhanced control devices. This study theoretically proved an intrinsic effect, namely, the input energy reduction, that the inerter reduces the input energy transmitted into the controlled structures from ground motion. A generic tuned mass damper inerter (GTMDI) including two separating inerters (the total inertance keeps constant) is analyzed to facilitate a universal analysis of typical inerter-based tuned mass dampers. Closed-form displacement and power equations are derived for the GTMDI to reveal and