Identification of an equivalent viscous damping function depending on engineering demand parameters
TL;DR: In this article, an evolving equivalent viscous damping ratio for a simply supported reinforced concrete beam is estimated for a reinforced concrete structure in the scope of a moderate seismicity context for which steel yielding is not expected.
About: This article is published in Engineering Structures.The article was published on 2019-06-01 and is currently open access. It has received 16 citations till now. The article focuses on the topics: Curvature.
Citations
More filters
TL;DR: In this article, the authors provide an overview of nonlinear damping identification (NDI) methods by explaining the fundamental challenges and potentials of these methods based on the available literature.
Abstract: In recent decades, nonlinear damping identification (NDI) in structural dynamics has attracted wide research interests and intensive studies. Different NDI strategies, from conventional to more advanced, have been developed for a variety of structural types. With apparent advantages over classical linear methods, these strategies are able to quantify the nonlinear damping characteristics, providing powerful tools for the analysis and design of complex engineering structures. Since the current trend in many applications tends to more advanced and sophisticated applications, it is of great necessity to work on developing these methods to keep pace with this progress. Moreover, NDI can provide an effective and promising tool for structural damage detection purposes, where the changes in the dynamic features of structures can be correlated with damage levels. This review paper provides an overview of NDI methods by explaining the fundamental challenges and potentials of these methods based on the available literature. Furthermore, this research offers a comprehensive survey of different applications and future research trends of NDI. For potential development and application work for nonlinear damping methods, the anticipated results and recommendations of the current paper can assist researchers and developers worldwide to find out the gaps and unsolved issues in the field of NDI.
19 citations
9 citations
Cites background from "Identification of an equivalent vis..."
...2), the general solution of Equation (15) can be expressed in Equations (16)–(18), and the damping ratio (ξ) can be determined in terms of Equation (19)(11,13):...
[...]
TL;DR: In this paper, a steel frame composed of a self-centering I-beam is proposed, with its capacities for selfcentering and inelastic deformation provided by post-tensioned (PT) strands and energy dissipating (ED) elements, respectively.
8 citations
6 citations
TL;DR: In this paper, the authors proposed a material-specific damping parameter based on the Bernoulli-Euler beam theory, which can be used to obtain the structure-specific stiffness parameters of a particular dynamic system.
5 citations
Cites background from "Identification of an equivalent vis..."
...[37] proposed an equivalent evolving viscous damping ratio to model nonlinear damped structures....
[...]
References
More filters
TL;DR: A mathematical representation of the multiaxial Bauschinger effect of materials at high temperatures was presented in this paper. But the model was not considered in this paper, nor in the paper.
Abstract: (2007) A mathematical representation of the multiaxial Bauschinger effect Materials at High Temperatures: Vol 24, No 1, pp 1-26
1,583 citations
Book•
01 Jan 2005
TL;DR: In this article, the authors present a set of structural and structural design rules for concrete and steel-concrete buildings with respect to the effects of seismic action on fixed base and isolated base.
Abstract: Chapter 1. Introduction Chapter 2. Performance requirements and compliance criteria, 2.1 Performance requirements for new designs in Eurocode 8 and associated seismic hazard levels, 2.2 Compliance criteria for the performance requirements and their implementation, 2.3 Exemption from the application of Eurocode 8 Chapter 3. Seismic Actions, 3.1 Ground conditions, 3.2 Seismic action,3.3 Displacement Response Spectra Chapter 4. Design of Buildings, 4.1 Scope, 4.2 Conception of structures for earthquake resistant buildings, 4.3 Structural regularity and implications for the design, 4.4 Combination of gravity loads and other actions with the design seismic action, 4.5 Methods of analysis, 4.6 Modeling of buildings for linear analysis, 4.7 Modeling of buildings for nonlinear analysis, 4.8 Analysis for accidental torsional effects, 4.9 Combination of the effects of the components of the seismic action, 4.10 "Primary" vs. "secondary" seismic elements, 4.11 Verifications, 4.12 Special rules for frame systems with masonry infills Chapter 5. Design and detailing rules for concrete buildings, 5.1 Scope, 5.2 Types of concrete elements-Definition of their "critical regions", 5.3 Types of structural systems for earthquake resistance of concrete buildings, 5.4 Design concepts: Design for strength or for ductility and energy dissipation-Ductility Classes, 5.5 Behaviour factor q of concrete buildings designed for energy dissipation, 5.6 Design strategy for energy dissipation, 5.7 Detailing rules for local ductility of concrete members, 5.8 Special rules for large walls in structural systems of large lightly reinforced walls, 5.9 Special rules for concrete systems with masonry or concrete infills, 5.10 Design and detailing of foundation elements Chapter 6. Design and detailing rules for steel buildings, 6.1 Scope, 6.2 Dissipative versus low dissipative structures, 6.3 Capacity design principle, 6.4 Design for local energy dissipation in the elements and their connections, 6.5 Design rules aiming at the realisation of dissipative zones, 6.6 Background of the deformation capacity required by Eurocode 8, 6.7 Design against localization of strains, 6.8 Design for global dissipative behaviour of structures, 6.9 Moment resisting frames, 6.10 Frames with concentric bracings, 6.11 Frames with eccentric bracings, 6.12 Moment resisting frames with infills, 6.13 Control of design and construction Chapter 7. Design and detailing of composite steel-concrete buildings, 7.1 Introductory remark, 7.2 Degree of composite character, 7.3 Materials, 7.4 Design for local energy dissipation in the elements and their connections, 7.5 Design for global dissipative behaviour of structures, 7.6 Properties of composite sections for analysis of structures and for resistance checks, 7.7 Composite connections in dissipative zones, 7.8 Rules for members, 7.9 Design of columns, 7.10 Steel beams composite with slab, 7.11 Design and detailing rules for moment frames, 7.12 Composite concentrically braced frames, 7.13 Composite eccentrically braced frames, 7.14 Reinforced concrete shear walls composite with structural steel elements, 7.15 Composite or concrete shear walls coupled by steel or composite beams, 7.16 Composite steel plates shear walls Chapter 8. Design and detailing rules for timber buildings, 8.1 Scope, 8.2 General concepts in earthquake resistant timber buildings, 8.3 Materials and properties of dissipative zones, 8.4 Ductility classes and behaviour factors, 8.5 Detailing, 8.6 Safety verifications Chapter 9. Seismic design with base isolation, 9.1 Introduction, 9.2 Dynamics of seismic isolation, 9.3 Design criteria, 9.4 Seismic isolation systems and devices, 9.5 Modelling and analysis procedures, 9.6 Safety criteria and verifications, 9.7 Design seismic action effects on fixed base and isolated buildings Chapter 10. Foundations, retaining structures and geotechnical aspects, 10.1 Introduction, 10.2 Seismic action, 10.3 Ground properties, 10.4 Requ
1,268 citations
TL;DR: In this article, a relatively simple nonlinear method for the seismic analysis of structures (the N2 method) is presented, which combines the pushover analysis of a multi-degree-of-freedom (MDOF) model with the response spectrum analysis of an equivalent single degree-offreedom (SDOF) system.
Abstract: A relatively simple nonlinear method for the seismic analysis of structures (the N2 method) is presented. It combines the pushover analysis of a multi‐degree‐of‐freedom (MDOF) model with the response spectrum analysis of an equivalent single‐degree‐of‐freedom (SDOF) system. The method is formulated in the acceleration‐displacement format, which enables the visual interpretation of the procedure and of the relations between the basic quantities controlling the seismic response. Inelastic spectra, rather than elastic spectra with equivalent damping and period, are applied. This feature represents the major difference with respect to the capacity spectrum method. Moreover, demand quantities can be obtained without iteration. Generally, the results of the N2 method are reasonably accurate, provided that the structure oscillates predominantly in the first mode. Some additional limitations apply. In the paper, the method is described and discussed, and it basic derivations are given. The similarities a...
955 citations
TL;DR: In this paper, the damping forces generated by such a matrix can become unrealistically large compared to the restoring forces, resulting in an analysis being unconservative, and a remedy to these problems is proposed in which bounds are imposed on the dampings forces.
Abstract: Rayleigh damping is commonly used to provide a source of energy dissipation in analyses of structures responding to dynamic loads such as earthquake ground motions In a finite element model, the Rayleigh damping matrix consists of a mass-proportional part and a stiffness-proportional part; the latter typically uses the initial linear stiffness matrix of the structure Under certain conditions, for example, a non-linear analysis with softening non-linearity, the damping forces generated by such a matrix can become unrealistically large compared to the restoring forces, resulting in an analysis being unconservative Potential problems are demonstrated in this paper through a series of examples A remedy to these problems is proposed in which bounds are imposed on the damping forces Copyright © 2005 John Wiley & Sons, Ltd
288 citations
TL;DR: In this paper, the effect of Rayleigh proportional damping in the analysis of inelastic structural systems is investigated, and it is shown that when the stiffness portion of the system damping matrix is based on the original system stiffness, artificial damping is generated when the structure yields.
Abstract: This paper investigates the consequence of using Rayleigh proportional damping in the analysis of inelastic structural systems. The discussion is presented theoretically, as well as by example through the analysis of a simple five-story structure. It is shown that when the stiffness portion of the system damping matrix is based on the original system stiffness, artificial damping is generated when the structure yields. When the damping matrix is based on the tangent stiffness but the Rayleigh proportionality constants are based on the initial stiffness, a significant but reduced amplification of damping occurs. When the damping is based on the tangent stiffness and on updated frequencies based on this stiffness, virtually no artificial damping occurs. The paper also investigates the influence on effective damping when localized yielding occurs in areas of concentrated inelasticity. In such cases, it is possible to develop artificial viscous damping forces that are extremely high, but that are not easy to detect. Such artificial damping forces may lead to completely invalid analysis. The paper ends with recommendations for performing analysis where the artificial damping is eliminated, or at least controlled.
279 citations