Investigation the Behavior of a Four-Storey Steel Frame Using Viscous Damper

2015 ◽  
Vol 735 ◽  
pp. 149-153 ◽  
Author(s):  
Meisam Gordan ◽  
Ahmad Haddadiasl ◽  
Abdul Kadir Marsono ◽  
Masine Md Tap
Keyword(s):  
Structural Damage ◽  
Experimental Tests ◽  
Steel Frame ◽  
Shaking Table ◽  
Dynamic Responses ◽  
Viscous Damper ◽  
Sea Waves ◽  
Damping Characteristics ◽  
Tall Structures ◽  
Structural Responses

Vibration is a serious concern for tall structures during a natural disaster such as earthquake, wind storms, sea waves and hurricanes. The risk of occurrence of structural damage can be decreased by using a controlled vibration system to increase the damping characteristics of a structure. Damping is defined as the ability of the structure to dissipate a portion of the energy released during a dynamic loading event. The aims of this study are (1) to investigate a 4-storey 2D steel frame retrofit with viscous damper to reduce its vibration and (2) to demonstrate the performance of such a damper when fitted to a structure by analysis and tests the model. Therefore, a series of shaking table tests of the 4-storey 2D steel frame with and without viscous damper (VD) was carried out to evaluate the performance of the structure. The results of the experimental tests illustrate that viscous dampers decrease the structural responses of slender frame without changing their behavior on the shaking table. In other words, the displacement of the structure is reduced, however, there is no any transition of flexible to stiff structure related to its dynamic responses.

scholarly journals Experimental Research on Passive Control of Steel Frame Structure Using SMA Wires

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Shi Yan ◽  
Jian Niu ◽  
Peng Mao ◽  
Gangbing Song ◽  
Wei Wang
Keyword(s):  
Passive Control ◽  
Shaking Table Test ◽  
Steel Frame ◽  
Shaking Table ◽  
Dynamic Responses ◽  
Frame Structure ◽  
Seismic Load ◽  
Control Effect ◽  
Maximum Displacement ◽  
Steel Frame Structure

Mechanical properties of shape memory alloy (SMA) wires were experimentally researched in this paper, and an energy dissipater made of SMA wire cable was designed and applied in a steel frame structure model by using superelasticity characteristics of SMAs to passively reduce dynamic responses of the steel frame structure under seismic load. For the characteristics of large relative displacements between the stories of the steel frame structure on both diagonal ends and the consideration of initial prestrain effects of the SMA cables, three kinds of the whole control, the part control, and no control of the shaking table tests and numerical simulations were carried, respectively. Through the results of the shaking table test and numerical simulation analysis, the dynamic responses such as the maximum displacement, velocity, and acceleration at the top layer of the steel frame structure applied with SMA cables are significantly decreased compared with the no control case. However, considering the premise of both effectiveness and efficiency, the part control effect is superior to the whole control. In many cases, it can meet the control requirement of reducing the maximum displacement and acceleration, while the superelasticity of SMAs can be sufficiently played, realizing the passive control purposes of the steel frame structure based on the energy dispassion through the application of the SMA cables. The proposed method has broad application prospects in the passive control field of building structures.

Structural Seismic Damage Detection Using Fractal Dimension of Time-Frequency Feature

2013 ◽  
Vol 558 ◽  
pp. 554-560 ◽  
Author(s):  
Dong Wang Tao ◽  
Dong Yu Zhang ◽  
Hui Li
Keyword(s):  
Fractal Dimension ◽  
Structural Damage ◽  
Nonlinear Behavior ◽  
Fractal Dimensions ◽  
Seismic Damage ◽  
Shaking Table ◽  
Dynamic Responses ◽  
Structural Dynamic ◽  
Time Frequency ◽  
Frequency Feature

In this paper, a data-driven approach to localizing structural damage subjected to ground motion is proposed by using the fractal dimension of the time-frequency features of structural dynamic responses. The time-frequency feature is defined as the real part of wavelet coefficient and the fractal dimension adopts the box-counting method. It is shown that the proposed fractal dimensions at each story of linear system are identical, while the fractal dimension at the stories with nonlinearity is different from those at the stories with linearity. Therefore, the nonlinear behavior of structural damage caused by strong ground motions can be detected and localized through comparing the fractal dimensions of structural responses at different stories. Shaking table test on a uniform 16-story 3-bay steel frame with added friction dampers modelling interstory nonlinear behavior was conducted. The experiment results validate the effectiveness of the proposed method to localize single and multi seismic damage of structures.

Experimental Investigation on Performance of Multiple Direction Optimized-Friction Pendulum System With Multiple Sliding Interfaces in Mitigating Structural Responses During Earthquakes

2011 ◽  
Author(s):  
C. S. Tsai ◽  
C. I. Hsueh ◽  
H. C. Su
Keyword(s):  
Experimental Tests ◽  
Shaking Table ◽  
Shaking Table Tests ◽  
Shear Forces ◽  
Pendulum System ◽  
Steel Building ◽  
Sliding Interfaces ◽  
Structural Responses ◽  
Friction Pendulum ◽  
Friction Pendulum System

This paper is aimed at the performance evaluation of the multiple direction-optimized friction pendulum system (MDO-FPS) with multiple sliding interfaces on seismic mitigation through a series of shaking table tests of a full scale building isolated with MDO-FPS isolators. Experimental tests of a three-story steel building of 40 tons in total weight, 3m and 4.5m in length and width, respectively, in two horizontal directions and 9m in height, subjected to various types of earthquakes were carried out to investigate the efficiency of the isolators in reducing structural responses during earthquakes. Results obtained from the shaking table tests demonstrate that the roof accelerations, base shears, column shear forces have been remarkably reduced while compared to the responses of a traditionally designed structure.

Isolating the effect of ground-motion duration on structural damage and collapse of steel frame buildings

2020 ◽  
Vol 36 (2) ◽  
pp. 718-740
Author(s):  
Esra Zengin ◽  
Norman A Abrahamson ◽  
Sashi Kunnath
Keyword(s):  
Ground Motion ◽  
Structural Damage ◽  
Damage Index ◽  
Structural Response ◽  
Steel Frame ◽  
Limit States ◽  
Long Duration ◽  
Frame Buildings ◽  
Steel Frame Buildings ◽  
Structural Responses

The debate over the significance of ground-motion duration is long-standing and the literature on the influence of duration on structural response is extensive. Decoupling of the duration from other characteristics of the ground motion is crucial for accurate quantification of its effect on structural responses. This article presents a new methodology that isolates the duration from the amplitude, frequency content, and rate of energy build-up of the ground motion. This is achieved by selecting short- and long-duration record pairs that are equated on the basis of spectral shape and the slope of the Husid plot. The use of the initial rate of Arias Intensity as a control parameter is novel in the literature. The proposed approach enables the examination of the sole effect of the duration on structural responses of 2-story and 9-story steel frame buildings. We find that the maximum interstory-drift ratios are not generally sensitive to the duration differences between short- and long-duration record sets, whereas the cumulative damage parameters (i.e. dissipated hysteretic energy and Modified Park–Ang Damage Index) of the buildings considered in this study are affected by duration. Finally, we extend the study to collapse limit states and find that duration has a small effect on structural collapse capacity, after controlling three key ground-motion parameters.

Spectral Analysis and Experimental Validation of a Low-Damage Hybrid Dissipater

2018 ◽  
Vol 763 ◽  
pp. 1007-1013
Author(s):  
Farzin G. Golzar ◽  
Geoffrey W. Rodgers ◽  
J. Geoffrey Chase
Keyword(s):  
Spectral Analysis ◽  
Structural Damage ◽  
Experimental Tests ◽  
Vital Role ◽  
Response Force ◽  
Viscous Damper ◽  
Damping Force ◽  
Experimental Proof ◽  
Hybrid Device ◽  
The Impact

Supplemental dissipation plays a vital role in reducing structural damage, repair costs, and downtime due to earthquakes. A hybrid dissipation mechanism has been developed to offer repeatable and consistent energy dissipation, while maintaining significant re-centring capability. This dissipation device consists of a viscous damper (VD) and a friction ring-spring (RS) combining rate-dependent dissipative behaviour of the viscous device with rate-independent dissipation and re-centring from the ring-spring. This approach, ensures simultaneous displacement reduction and increased self-centring potential. Spectral analysis of a single-degree-of-freedom structure has been carried out to outline the efficacy of the device and delineate the impact and contribution of each component to the overall device behaviour. A prototype hybrid device is tested comprising a viscous damper with silicone fluid and a ring-spring with peak design force of 26kN. These components are connected in a parallel configuration through a fixed outer shell and a moving coupled shaft. Experimental proof-of-concept testing for the hybrid device and single ring-spring includes sinusoidal displacement inputs with amplitude of 25 and 30 mm, loading frequencies of [0.25-1.75] Hz, and ring-spring pre-load of 21 and 34%. The overall device has a peak response force of 32kN at input velocities of ~200 mm/s. At this speed, ~20kN comes from the ring spring and ~12kN from the viscous damper. Further tests on the single viscous device are conducted using silicone oils with viscosities of 100, 500, and 1000 cSt and peak input velocities of [50-300] mm/s to evaluate the impact of viscosity on the damping force. These experimental tests are used to delineate the function of the individual components of the device and assess the behaviour of the hybrid combination, in comparison to the predicted analytical behaviour.

scholarly journals Seismic Performance of Ni-Ti SMA Wires Equipped in the Spatial Skeletal Structure

2021 ◽  
Vol 8 ◽  
Author(s):  
Yang Liu ◽  
Tao Yang ◽  
Binbin Li ◽  
Bo Liu ◽  
Wentao Wang ◽  
...  
Keyword(s):  
Numerical Model ◽  
Vibration Control ◽  
Seismic Performance ◽  
Passive Control ◽  
Shaking Table Test ◽  
Experimental Tests ◽  
Shaking Table ◽  
Dynamic Responses ◽  
Skeletal Structure ◽  
Performance Study

Nickel Titanium (Ni-Ti) Shape Memory Alloy (SMA) can be used to limit response of structure during external disturbances such as large seismic events. This paper presents a seismic performance study of Ni-Ti SMA wires equipped in the spatial skeletal structure. First, an improved Graesser-Cozzarelli (G-C) numerical constitutive model of the Austenitic phase of NiTi SMA wire is established. By contrast, the model based on uniaxial cyclic loading experimental tests is demonstrated as feasibility and validity. Next, a method consisting of a three-layer steel spatial skeletal structure model equipped with SMA wires is employed for simulation and experimental tests. According to the obtained constitutive numerical model, the simulation program of vibration control is written to simulate the effect of vibration control of seismic EL-centro wave. Furthermore, a shaking table experimental test was designed to verify the vibration control effect under the same action of seismic EL-centro wave. By comparison of the results of the numerical simulation and shaking table test, dynamic responses of the displacement and acceleration for different floors with control and without control was concluded. The superior superelastic properties of SMA wires used in passive control are investigated and the correctness of the constitutive numerical model are verified as well. The results show that such a comprehensive analysis integrates seismic-resistant behavior of Ni-Ti SMA wires in this type of structure. Besides, proposed method has broad application prospects to address the issues in passive control field of building structures.

scholarly journals Damage Diagnosis in 3D Structures Using a Novel Hybrid Multiobjective Optimization and FE Model Updating Framework

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Nizar Faisal Alkayem ◽  
Maosen Cao ◽  
Minvydas Ragulskis
Keyword(s):  
Structural Damage ◽  
Model Updating ◽  
Complex Problem ◽  
Dynamic Responses ◽  
Mode Shapes ◽  
Fe Model ◽  
Modal Strain Energy ◽  
3D Structures ◽  
Multiobjective Particle Swarm Optimization ◽  
Damage Tracking

Structural damage detection is a well-known engineering inverse problem in which the extracting of damage information from the dynamic responses of the structure is considered a complex problem. Within that area, the damage tracking in 3D structures is evaluated as a more complex and difficult task. Swarm intelligence and evolutionary algorithms (EAs) can be well adapted for solving the problem. For this purpose, a hybrid elitist-guided search combining a multiobjective particle swarm optimization (MOPSO), Lévy flights (LFs), and the technique for the order of preference by similarity to ideal solution (TOPSIS) is evolved in this work. Modal characteristics are employed to develop the objective function by considering two subobjectives, namely, modal strain energy (MSTE) and mode shape (MS) subobjectives. The proposed framework is tested using a well-known benchmark model. The overall strong performance of the suggested method is maintained even under noisy conditions and in the case of incomplete mode shapes.

scholarly journals Influence of Structure on the Aseismic Stability and Dynamic Responses of Liquefiable Soil

2021 ◽  
Author(s):  
Pengfei Dou ◽  
Chengshun Xu ◽  
Xiuli Du ◽  
Su Chen
Keyword(s):  
Earthquake Engineering ◽  
Damping Ratio ◽  
Free Field ◽  
Shaking Table ◽  
Dynamic Responses ◽  
Seismic Stability ◽  
Geotechnical Earthquake Engineering ◽  
Liquefiable Soil ◽  
Porewater Pressure ◽  
Lateral Displacements

Abstract In previous major earthquakes, the damage and collapse of structures located in liquefied field which caused by site failure a common occurrence, and the problem of evaluation and disscusion on site liquefaction and the seismic stability is still a key topic in geotechnical earthquake engineering. To study the influence of the presence of structure on the seismic stability of liquefiable sites, a series of shaking table tests on liquefiable free field and non-free field with the same soil sample was carried out. It can be summarized from experimental results as following. The natural frequency of non-free field is larger and the damping ratio is smaller than that of free field. For the weak seismic loading condition, the dynamic response of sites show similar rules and trend. For the strong ground motion condition, soils in both experiments all liquefied obviously and the depth of liquefaction soil in the free field is significantly greater than that in the non-free field, besides, porewater pressure in the non-free field accumulated relately slow and the dissapited quikly from analysis of porewater pressure ratios(PPRs) in both experiments. The amplitudes of lateral displacements and acceleration of soil in the non-free field is obviously smaller than that in the free field caused by the effect of presence of the structure. In a word, the presence of structures will lead to the increase of site stiffness, site more difficult to liquefy, and the seismic stability of the non-free site is higher than that of the free site due to soil-structure interaction.

Sign in / Sign up

Export Citation Format

Share Document