Invited Review: Recent developments in vibration control of building and bridge structures

This paper presents a state-of-the-art review of recent articles published on active, passive, semi-active and hybrid vibration control systems for structures under dynamic loadings primarily since 2013. Active control systems include active mass dampers, active tuned mass dampers, distributed mass dampers, and active tendon control. Passive systems include tuned mass dampers (TMD), particle TMD, tuned liquid particle damper, tuned liquid column damper (TLCD), eddy-current TMD, tuned mass generator, tuned-inerter dampers, magnetic negative stiffness device, resetting passive stiffness damper, re-entering shape memory alloy damper, viscous wall dampers, viscoelastic dampers, and friction dampers. Semi-active systems include tuned liquid damper with floating roof, resettable variable stiffness TMD, variable friction dampers, semi-active TMD, magnetorheological dampers, leverage-type stiffness controllable mass damper, semi-active friction tendon. Hybrid systems include shape memory alloys-liquid column damper, shape memory alloy-based damper, and TMD-high damping rubber

Artificial Intelligence Approach for Seismic Control of Structures

Abstract In the first part of this research, the utilization of tuned mass dampers in the vibration control of tall buildings during earthquake excitations is studied. The main issues such as optimizing the parameters of the dampers and studying the effects of frequency content of the target earthquakes are addressed. Abstract The non-dominated sorting genetic algorithm method is improved by upgrading generic operators, and is utilized to develop a framework for determining the optimum placement and parameters of dampers in tall buildings. A case study is presented in which the optimal placement and properties of dampers are determined for a model of a tall building under different earthquake excitations through computer simulations. Abstract In the second part, a novel framework for the brain learning-based intelligent seismic control of smart structures is developed. In this approach, a deep neural network learns how to improve structural responses during earthquake excitations using feedback control. Abstract Reinforcement learning method is improved and utilized to develop a framework for training the deep neural network as an intelligent controller. The efficiency of the developed framework is examined through two case studies including a single-degree-of-freedom system and a high-rise building under different earthquake excitation records. Abstract The results show that the controller gradually develops an optimum control policy to reduce the vibrations of a structure under an earthquake excitation through a cyclical process of actions and observations. Abstract It is shown that the controller efficiently improves the structural responses under new earthquake excitations for which it was not trained. Moreover, it is shown that the controller has a stable performance under uncertainties

Semi-Active Control Systems in Bridge Engineering: A Review of the Current State of Practice

In view of the grave socioeconomic consequences of earthquake damage to bridge structures, along with their critical role in modern and older road and rail networks, this article attempts to identify and summarise the current trends in the use of semi-active control technology in bridge engineering, as an enhanced seismic response control solution, combining increased adaptability and reliability, compared to passive and active schemes. In this context, representative analytical and experimental studies, as well as some full-scale applications of semi-active control devices are first reviewed and a brief description of relevant benchmark studies is subsequently presented, with a view to serving as a point of reference for further research and development. A framework of performance-based control principles aiming at the aforementioned objectives is finally set forth

Passive, semi-active, active and hybrid mass dampers: A literature review with associated applications on building-like structures

In this paper, a state-of-the-art literature review is presented emphasising on the development of control variants for mass damper schemes on building-like structures. Additionally, a systematic literature review is conducted addressing three relevant questions: What type of mass damper is preferable by the associated industry? How are mass dampers distributed around the world? Is industry following research? Through the systematic literature review, updated lists of mass damper implementations and control algorithm applications in real-life structures were compiled. 208 case-studies are discussed in total. It is found that, 63% of them refer to passive tuned mass dampers, 31% to hybrid mass dampers, 4.0% to active mass dampers and only 2% to semi-active mass dampers. Regarding control algorithms, controllers of 24 structures driving semi-active, active or hybrid mass dampers are presented. It is concluded that the industry considerably lags behind latest structural control research both regarding implementations and overall management

Structural systems with suspended and self-centered floor slabs for earthquake resistance

2013 Summer.Includes bibliographical references.The purpose of this study is to develop a novel structural system for mitigating the effects of earthquakes on building systems by suspending the concrete floor slabs of a steel building. The slab is suspended using hanger rods and act as Tune Mass Dampers (TMDs) to reduce the response of the structural system. In addition, steel links are added between the bottom face of the suspended slab and the beam below the slab and are used as energy dissipaters during an earthquake. Moreover, post-tensioned cables are installed adjacent to the steel links to provide a self-centering capability to the floor slab and eliminate residual drift after a seismic event. The Suspended Slab (SS) system is analyzed by constructing suitable theoretical models, from which mathematical equations describing the response of the system are developed and analyzed The location and number of suspended slabs and energy dissipation links needs to be carefully chosen for optimum performance of the system. To find the optimized condition, the simple optimization approach of Numerical Search is used. The optimization identifies the best locations, damping ratio and the frequency ratio of the slabs. The approach is suitable for short structures, however with increase in number of floors the algorithm becomes time costly. A new combinatorial approach of optimization is implemented that uses Nelder Mead algorithm and Covariance Matrix Adaptation Evolution Strategy. The new optimization is modified and tested to assess its effectiveness. Finally, three test structures are utilized to evaluate the effectiveness of the suspended slab system using the combinatorial optimization approach. The earthquake is modeled as a stationary white noise and Kanai Tajimi Spectrum is used as excitation input to obtain the Root Mean Square response, which is considered as the performance evaluation parameter. From the results of this study it is concluded that the suspended slab system can be quite an effective strategy for earthquake mitigation

Efficient estimation of tuned liquid column damper inerter (TLCDI) parameters for seismic control of base-isolated structures

This paper presents an enhanced base-isolation (BI) system equipped with a novel passive control device composed of a tuned liquid damper and an inerter (TLCDI). With the aim of reducing the seismic response of BI systems, this contribution focuses on the design of the TLCDI providing analytical solutions for the optimal TLCDI parameters, easily implementable in the design phase. The effectiveness of the proposed approach in terms of seismic response reduction and computational gain is validated by comparison with classical numerical optimization techniques. The control performance of two different base-isolated TLCDI-controlled structures is assessed by employing real-ground motion records, and relevant comparisons with both uncontrolled base-isolated structures and equipped with a conventional TLCD are presented