Nonlinear dynamic analysis for multi-storey RC structures with hybrid base isolation systems in presence of bi-directional ground motions

During the past decade the need to perform nonlinear static and dynamic analyses on bridge structures has increased significantly. Nonlinear dynamic analysis has become the approach that is used when protective systems such as base isolators and isolation systems are present in the bridge structure. The commercial computer programs available that are used for these types of analyses and that can be understood and used by structural bridge engineers have been far from adequate. Recently, the research community has produced a number of useful computer programs. Among these are the IDARC-Bridge and 3D-BASIS family of programs from the State University of New York at Buffalo. Bridge engineers are not usually familiar with the available computer codes primarily used by researchers, and it is generally known that these programs are not user friendly. Prediction of the nonlinear dynamic responses of bridge structures has presented other challenges. These range from the volume of input and output to the computational effort needed to obtain solutions. The increase in computer speed and the use of faster-solution algorithms have drastically reduced the time needed to perform iterative nonlinear dynamic analysis. Use of the Microsoft Windows-based standardized graphical user interface with the ability for the seamless exchange of data between programs makes the volume of input and output manageable. The implementation of 3D-BASIS-ME—type nonlinear base isolators and isolation systems and the analysis methods used in the family of Microsoft Windows-based software LARSA, with which bridge engineers have become familiar over the years using a wide range of applications for bridges and buildings, are presented.

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A New Passive Seismic Control Device for Protection of Structures under Anomalous Seismic Events

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.82.651 ◽

2011 ◽

Vol 82 ◽

pp. 651-656 ◽

Cited By ~ 4

Author(s):

Donato Cancellara ◽

Mario Pasquino

Keyword(s):

Dynamic Analysis ◽

Nonlinear Dynamic ◽

Base Isolation ◽

Nonlinear Dynamic Analysis ◽

Control Device ◽

Hysteretic Behavior ◽

Isolation System ◽

Seismic Control ◽

Seismic Isolator ◽

Seismic Force

In this paper, the possibility offered by the Base Isolation System, designed according to the strategy of limitation seismic force, in order to ensure a significant level of robustness to the isolated superstructure, has been analyzed. In according to the strategy of limitation seismic force, a new seismic isolator called HDHSI (High Damping Hybrid Seismic Isolator) is proposed, obtained by the assembly in series of a LRB (Lead Rubber Bearing) and a FS (Friction Slider) with high friction coefficient. The HDHSI device is in contrast to the R-FBI (Resilient-Friction Base Isolation) isolator and is the optimization of the EDF (Electricité De France) system. A modeling with HDHSI devise has been presented by using nonlinear finite elements NLlink (Nonlinear link) and nonlinear dynamic analysis for a SDOF system with harmonic force, in order to characterize the cycle-hysteretic behavior of the device for different levels of shear deformation, are performed. Nonlinear dynamic analysis for a RC structure, base isolated by the proposed devices, are performed. As seismic actions, have been adopted the following registrations: an anomalous earthquakes for intensity and in particular El Centro earthquake (N00W component, 1940) with different amplification factors; an anomalous earthquake for frequency content and in particular Erzincan earthquake (N90W component, 1992).

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Análisis no lineal de la estructura del Hospital Darío Machuca Palacios del cantón La Troncal en Ecuador

KnE Engineering ◽

10.18502/keg.v3i1.1434 ◽

2018 ◽

Vol 3 (1) ◽

pp. 292

Author(s):

Francisco Xavier Calle Guaraca ◽

Bernardo Andrés Feijoo Guevara ◽

Ing. José Fernando Vásquez Calero, M.Sc

Keyword(s):

Dynamic Analysis ◽

Nonlinear Dynamic ◽

Seismic Isolation ◽

Nonlinear Dynamic Analysis ◽

Seismic Protection ◽

Isolation Systems ◽

Seismic Isolation Systems

The hospital "Darío Machuca Palacios" is located in La Troncal (Cañar-Ecuador). In the nonlinear dynamic analysis of this hospital was determined inconsistencies in its design, such as non-compliance with maximum permissible drifts established by the Ecuadorian Construction Standard (NEC, as per its Spanish acronym), demonstrating vulnerability and possible collapse of the hospital. Considering that it is an essential building according to the NEC of seismic danger, it needs to be maintained in correct post-earthquake operation. For this reason the behavior of the structure with seismic isolation systems at their base was simulated, offering results that analyzed in depth could determine that this measure of seismic protection is adequate.Keywords: nonlinear dynamic analysis, essential building, seismic isolation systems.

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