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The equivalent viscous damping is a key parameter in the prediction of the maximum nonlinear response. Damping constitutes a major source of uncertainty in dynamic analysis. This paper studies the effect of using viscous damping, on the reduction of the seismic responses of reinforced concrete RC frame buildings modeled as three-dimensional multi d...
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The present study investigates the seismic behavior of multi storey building retrofitted with damping devices located within the lateral load resisting elements (core wall). The study concentrates on a retrofitting strategy with passive energy dissipation devices known as Fluid Viscous Dampers (FVDs) in diagonal configuration. A 3D model of a twent...
This paper investigates the seismic behavior of multi storey building using damping devices strategically located within the lateral load resisting elements (shear wall). The study concentrates on a retrofitting strategy with passive energy dissipation device known as Fluid Viscous Damper (FVD) which can be used to retrofit existing buildings to en...
This paper investigates the seismic behavior of multi storey building using damping devices strategically located within the lateral load resisting elements (shear wall). The study concentrates on a retrofitting strategy with passive energy dissipation device known as Fluid Viscous Damper (FVD) which can be used to retrofit existing buildings to en...
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... Soils are characterized by the shear wave velocity. The Algerian seismic code RPA99/Version 2003 [20][21] proposes to divide sites into four categories: very soft soil, soft soil, hard soil, and rocky soil. This classification was based on soil mechanical properties, primarily shear wave velocity. ...
It has been found that in the event of a strong earthquake, and due to insufficient distance between two adjacent structures, the lateral movement at the top of structures may cause collisions between them. This phenomenon, commonly known as seismic collision, can generate impact forces that were not considered during the initial design of the structure. These forces can cause significant structural damage or lead to complete collapse of the structure. The main purpose of this paper is to study the coupled effects of soil flexibility and impact between adjacent buildings undergoing seismic excitation. To capture the impact forces between the structures during the collision, a modified linear viscoelastic model was used effectively. Particular attention has been paid to studying the effects of shear wave velocity, first on the soil structure interaction and then on the collision response of adjacent structures. Three configurations of adjacent structures were analyzed: light-light, light-heavy, and heavy-heavy structures. The results obtained through this analysis showed that the dynamic response and the impact force of the structures depend essentially on the interaction between the structure, the foundation, and the soil.
... Some scholars have conducted extensive damper design and experiments, and used experimental data to determine the damping coefficient and damping characteristics of viscous dampers [1]; Some scholars have evaluated the impact of different viscous damper damping coefficients on the seismic response of towers by analyzing the impact of towers with different damper damping coefficients on low rise buildings [2]; Some scholars have conducted different types of simulations using modal analysis and seismic time history analysis, and obtained data that can determine the nonlinear characteristics of fluid dampers [3]; Some scholars even use genetic algorithm based search methods to test the optimal distribution of damping coefficients [4]. Scholars have also conducted research on the impact of viscous damping on low-rise reinforced concrete frame structures under earthquakes, compared the seismic evaluation of RC buildings with and without friction dampers, and studied the impact of friction damping isolation systems on the performance of prefabricated concrete buildings [5][6][7]. Through continuous research by scholars, various types of dampers have emerged, including a new type of seismic damper based on the yielding of cantilever metal components proposed by TS Ahn and other scholars [8], a magnetorheological (MR) grease damper proposed by T. Sakurai and other scholars [9], and a prestressed viscous damper (PVD) proposed by A Bogdanovic and other scholars [10]. ...
In this paper, the basic principle, secondary software development and practical application of viscous damper vibration reduction technology are studied. The viscous damping coefficient velocity function equivalence method is used, and the secondary development is carried out in the finite element software ANSYS through program compilation, and the operation interface of the velocity function equivalence method is established. On this basis, the complex vibration problems of an existing building are studied, and the arrangement and installation of viscous dampers are guided on site.Through comparative analysis, it is concluded that the UIDL program and APDL macro command stream in the finite element software ANSYS can be used to establish the operation interface of the speed function equivalent method, which makes the method have better applicability and operability, improve the work efficiency and facilitate the popularization and application. By adopting the nonlinear viscous damper damping technology, before the structure and equipment produce strong vibration, the damper first enters the energy dissipation state, produces large damping, greatly consumes vibration energy, and rapidly attenuates the dynamic response of the structure and equipment to ensure the safety and normal use of the structure and equipment.The field dynamic test results and the finite element analysis results both show that the viscous damper vibration reduction technology based on the velocity function equivalent method has a significant vibration reduction effect, and is an effective means to solve the existing building vibration problems.
... Parameter updates have, finally, been studied in L eger and Dussault (1992) and Jehel and L eger (2017). Then, to help engineers select a damping matrix formulation for seismic analyses, numerous papers have focused on comparing all those formulations (Abbasi & Moustafa, 2021;Anajafi et al., 2020;Baba-Hamed & Davenne, 2020;Bhattacharjee & Ghrib, 1995;Correia et al., 2013;Luu et al., 2013;Ryan & Polanco, 2008;Sousa et al., 2020). The conclusion shared by the majority has been to use tangent stiffness proportional damping or the Rayleigh damping formulation with the tangent stiffness matrix. ...
Earthquake events in recent years and their consideration in performance-based design have led to the development of increasingly sophisticated physical models in structural computations. The aim of such models has been to predict the structural behaviour when excited by an earthquake. In particular, in the context of nuclear power plants (high-risk structures), operators must justify the airtightness of ageing structures to study the nonlinear behaviours of these structures, requiring the study and modelling of the phenomena associated with seismic energy dissipation in concrete. Energy dissipation has been described at two levels: global and local scales. At the local scale, material behaviour laws express some phenomena, such as concrete damage, friction, unilateral effects or plasticity. At the global scale, for dynamic analyses, energy dissipation has been practically modelled with equivalent viscous damping. Rayleigh-type damping formulations are still the most commonly used in engineering. Numerous formulations have been proposed in the literature, and some papers have compared some of these formulations. However, comparisons have rarely been based on experimental data, and the structures studied have varied considerably among studies. Therefore, the first objective of this paper is to assess the accuracy of a wide range of damping formulations by comparing them to the experimental data. Reinforced concrete beams were tested in quasistatic mode on a strong floor and in dynamic mode on a shaking table. The aim was to study the energy dissipation involving nonlinear mechanisms in concrete while steel rebar remained in their elastic range. The study developed in this paper concerns the dynamic behaviour of reinforced concrete critical structures, which are over-sized in engineering, under moderate earthquake levels. Thus, a beam multifibre model is proposed with two different concrete constitutive models. The second objective is to compare the energy dissipation at structural and material scales to evaluate the most efficient damping formulations to represent dynamic nonlinear responses.
... Parameter updates have, finally, been studied in L eger and Dussault (1992) and Jehel and L eger (2017). Then, to help engineers select a damping matrix formulation for seismic analyses, numerous papers have focused on comparing all those formulations (Abbasi & Moustafa, 2021;Anajafi et al., 2020;Baba-Hamed & Davenne, 2020;Bhattacharjee & Ghrib, 1995;Correia et al., 2013;Luu et al., 2013;Ryan & Polanco, 2008;Sousa et al., 2020). The conclusion shared by the majority has been to use tangent stiffness proportional damping or the Rayleigh damping formulation with the tangent stiffness matrix. ...
This research paper presents an in-depth investigation into the seismic response of hybrid structures integrated with fluid viscous dampers (FVDs) and base isolation. Severe seismic events pose hazardous threats to hybrid structures, making it imperative to develop effective strategies for enhancing their seismic resilience. The study aims to assess the seismic performance of hybrid structures featuring Circular Hollow Section (CFST) and concrete-encased steel (CES) columns in comparison with conventional columns in RCC structures, leveraging the attributes of both FVDs and base isolation. Finite element analysis is employed to model the hybrid structure, and performance evaluation is conducted based on key parameters, including inter-story drifts, fundamental time period, stiffness, story displacements, base shear and overturning moments, utilizing the response spectrum approach. The study focuses on 16-story hybrid structures, having three different shapes of CFST and CES columns, incorporated individually with FVD, Lead Rubber Bearings (LRB) isolators, and a combination of both. To foster a more comprehensive understanding, the dampers are placed at two different heights, i.e., H and H/2 height of the building. The results demonstrate a noteworthy reduction in the structural response of the hybrid structure when subjected to seismic events through the integration of FVDs and base isolation. Comparative analysis of each energy-dissipating system reveals that a synergistic combination of FVDs and base isolation yields superior performance compared to their individual use. By bridging the existing research gap and investigating the intricate behavior of hybrid structures equipped with FVDs and base isolation, this research contributes significantly to the fields of earthquake engineering and structural resilience. The study contributes valuable insights into the advantages and limitations of each system, aiming to facilitate the development of safer and more resilient buildings, particularly in regions prone to high seismic activity.
