Evaluation of anchorage performance of the switchboard cabinet under seismic loading condition

In this study, the seismic response of the anchorage used for switchboard cabinets at a power plant was presented based on the results of an experiment and numerical simulations. In the experimental study, shaking table tests were performed to investigate the overall structural behavior of switchboard cabinets. The finite element modeling was conducted using the ABAQUS program, and in order to validate the proposed finite element model, the natural frequency, stress, and displacement were compared with the experimental results. A slight difference was found in the results due to the problem cup-like deformation at the anchorage of the bottom, but it showed reasonable agreement when considering the results for all behaviors. Using the proven model, nonlinear dynamic analysis was performed using three types of a period waves. The maximum stress on the anchorage occurred when a long-period wave was applied, and the horizontal maximum displacement of the cabinet was approximately 10 times greater than when an ultra-short-period wave was applied. It is expected that the flexibility of the cabinet stiffness resulted in more structural weakness, especially under a long-period wave, and that is recommended to focus on displacement rather than stress when establishing seismic design guidelines for switchboard cabinets.

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Development of Simulation Based p-Multipliers for Laterally Loaded Pile Groups in Granular Soil Using 3D Nonlinear Finite Element Model

Applied Sciences ◽

10.3390/app11010026 ◽

2020 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Muhammad Bilal Adeel ◽

Muhammad Asad Jan ◽

Muhammad Aaqib ◽

Duhee Park

Keyword(s):

Finite Element ◽

Element Model ◽

Design Guidelines ◽

American Petroleum Institute ◽

Winkler Foundation ◽

Group Effect ◽

Pile Groups ◽

Element Analysis ◽

Laterally Loaded Pile ◽

Laterally Loaded

The behavior of laterally loaded pile groups is usually accessed by beam-on-nonlinear-Winkler-foundation (BNWF) approach employing various forms of empirically derived p-y curves and p-multipliers. Averaged p-multiplier for a particular pile group is termed as the group effect parameter. In practice, the p-y curve presented by the American Petroleum Institute (API) is most often utilized for piles in granular soils, although its shortcomings are recognized. In this study, we performed 3D finite element analysis to develop p-multipliers and group effect parameters for 3 × 3 to 5 × 5 vertically squared pile groups. The effect of the ratio of spacing to pile diameter (S/D), number of group piles, varying friction angle (φ), and pile fixity conditions on p-multipliers and group effect parameters are evaluated and quantified. Based on the simulation outcomes, a new functional form to calculate p-multipliers is proposed for pile groups. Extensive comparisons with the experimental measurements reveal that the calculated p-multipliers and group effect parameters are within the recorded range. Comparisons with two design guidelines which do not account for the pile fixity condition demonstrate that they overestimate the p-multipliers for fixed-head condition.

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Wave Force Characteristics of Large-Sized Offshore Wind Support Structures to Sea Levels and Wave Conditions

Applied Sciences ◽

10.3390/app9091855 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1855

Author(s):

Youn-Ju Jeong ◽

Min-Su Park ◽

Jeongsoo Kim ◽

Sung-Hoon Song

Keyword(s):

Shallow Water ◽

Wave Height ◽

Wave Force ◽

Diffraction Effect ◽

Support Structures ◽

Sea Levels ◽

Irregular Wave ◽

Long Period ◽

Short Period ◽

Period Wave

This paper presents the results of wave force tests conducted on three types of offshore support structures considering eight waves and three sea levels to investigate the corresponding wave forces. As a result of this study, it is found that the occurrence of shoaling in shallow water induces a significant increase of the wave force. Most of the test models at the shallow water undergo a nonlinear increase of the wave force with higher wave height increasing. In addition, the larger the diameter of the support structure within the range of this study, the larger the diffraction effect is, and the increase in wave force due to shoaling is suppressed. Under an irregular wave at the shallow water, the wave force to the long-period wave tends to be slightly higher than that of the short period wave since the higher wave height component included in the irregular wave has an influence on the shoaling. In addition, it is found that the influence of shoaling under irregular wave becomes more apparent in the long period.

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Finite Element Analysis of the ESTELA M1 Airplane Firewall (Representative Specimen)

Volume 3: Design and Manufacturing ◽

10.1115/imece2011-64511 ◽

2011 ◽

Author(s):

V. Ramirez-Elias ◽

E. Ledesma-Orozco ◽

H. Hernandez-Moreno

Keyword(s):

Finite Element ◽

Federal Aviation Administration ◽

Element Model ◽

Maximum Load ◽

Load Factor ◽

Representative Specimen ◽

Maximum Displacement ◽

Element Analysis ◽

Element Simulation ◽

The Relationship

This paper shows the finite element simulation of a representative specimen from the firewall section in the AEROMARMI ESTELA M1 aircraft. This specimen is manufactured in glass and carbon / epoxy laminates. The specimen is subjected to a load which direction and magnitude are determined by a previous dynamic loads study [10], taking into account the maximum load factor allowed by the FAA (Federal Aviation Administration) for utilitarian aircrafts [11]. A representative specimen is manufactured with the same features of the firewall. Meanwhile a fix is built in order to introduce the load directions on the representative specimen. The relationship between load and displacement is plotted for this representative specimen, whence the maximum displacement at the specific load is obtained, afterwards it is compared with the finite element model, which is modified in its laminate thicknesses in order to decrease the deviation error; subsequently this features could be applied to perform the whole firewall analysis in a future model [10].

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Low Cost Frictional Seismic Base-Isolation of Residential New Masonry Buildings in Developing Countries: A Small Masonry House Case Study

The Open Civil Engineering Journal ◽

10.2174/1874149501711011026 ◽

2017 ◽

Vol 11 (1) ◽

pp. 1026-1035 ◽

Cited By ~ 9

Author(s):

Ahmad Basshofi Habieb ◽

Gabriele Milani ◽

Tavio Tavio ◽

Federico Milani

Keyword(s):

Finite Element ◽

Seismic Vulnerability ◽

Base Isolation ◽

Low Cost ◽

Element Model ◽

Shaking Table ◽

Fe Model ◽

Isolation System ◽

Finite Element Software ◽

Non Linear

Introduction:An advanced Finite Element model is presented to examine the performance of a low-cost friction based-isolation system in reducing the seismic vulnerability of low-class rural housings. This study, which is mainly numerical, adopts as benchmark an experimental investigation on a single story masonry system eventually isolated at the base and tested on a shaking table in India.Methods:Four friction isolation interfaces, namely, marble-marble, marble-high-density polyethylene, marble-rubber sheet, and marble-geosynthetic were involved. Those interfaces differ for the friction coefficient, which was experimentally obtained through the aforementioned research. The FE model adopted here is based on a macroscopic approach for masonry, which is assumed as an isotropic material exhibiting damage and softening. The Concrete damage plasticity (CDP) model, that is available in standard package of ABAQUS finite element software, is used to determine the non-linear behavior of the house under non-linear dynamic excitation.Results and Conclusion:The results of FE analyses show that the utilization of friction isolation systems could much decrease the acceleration response at roof level, with a very good agreement with the experimental data. It is also found that systems with marble-marble and marble-geosynthetic interfaces reduce the roof acceleration up to 50% comparing to the system without isolation. Another interesting result is that there was little damage appearing in systems with frictional isolation during numerical simulations. Meanwhile, a severe state of damage was clearly visible for the system without isolation.

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Finite Element Analysis of Mechanics Property on Memory Alloy Patella Claws with Anti-Shearing Force

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.635-637.507 ◽

2014 ◽

Vol 635-637 ◽

pp. 507-510

Author(s):

Dong Peng Du ◽

Zhe Wu ◽

Juan Xing ◽

Xiao Yan Gong ◽

Xiang Wen Miu ◽

...

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Mechanical Performance ◽

Tensile Force ◽

Research Result ◽

Element Model ◽

3D Models ◽

Shearing Force ◽

Maximum Displacement ◽

Element Analysis

When strong exercise on human being body, respectively, under knees 30°, 60°,90°, using PRO/E5.0 software to establish the transverse patella fracture and anti-shearing force patella claws 3D models, then the two structure models were assembled and imported into ABAQUS10.1 software to establish the finite element model of patellar fracture fixed within patella claw, and analyzed the mechanical performance in perforce finite element model. Under the same boundary conditions, the maximum displacement and deformation of each components were different at every flexion angle. Compared with anti-shearing force patella claw and AO tensile force girdle, the patella claw with stronger resistance to tension and anti-shearing force was more stable. Deformation and displacement of patella claw in accordance with biomechanical research result that is needed by clinical. Its stability will satisfy clinical requirements for functional exercise.

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An Artificial Seismic Wave Suitable for Suspended Converter Valve in the UHVDC Transmission Project

E3S Web of Conferences ◽

10.1051/e3sconf/201911802039 ◽

2019 ◽

Vol 118 ◽

pp. 02039

Author(s):

Jin Xiao ◽

Mingduo Huang ◽

Qiguo Sun

Keyword(s):

Finite Element ◽

Seismic Wave ◽

Seismic Design ◽

Response Spectrum ◽

Time History ◽

Element Model ◽

Series Method ◽

Long Period ◽

Standard Response ◽

The Finite Element Model

The finite element model of suspended converter valve in an UHVDC transmission project with characteristics of flexible is constructed, and its vibration characteristics are simulated and analyzed firstly. The results show that this kind of suspended converter valve has obvious long-period character. Secondly, the long period phase of standard response spectrum in Code for Seismic Design of Buildings (GB50011-2010) is modified, and then the artificial seismic wave is synthesized employing the triangular series method. The result shows that this artificial seismic wave has long-period character. Finally, the time-history seismic dynamic simulation of the converter valve is done, and the seismic responses of the converter valve excited by three kinds of seismic wave with different period characters are compared and analyzed. The results show that the swing and stress of the suspended converter valve are larger under the long-period seismic wave synthesized in this paper. The quasi-resonance damage caused by long-period seismic wave should be concerned specially in the actual UHVDC transmission project.

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A topology optimization method of robot lightweight design based on the finite element model of assembly and its applications

Science Progress ◽

10.1177/0036850420936482 ◽

2020 ◽

Vol 103 (3) ◽

pp. 003685042093648

Author(s):

Liansen Sha ◽

Andi Lin ◽

Xinqiao Zhao ◽

Shaolong Kuang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Topology Optimization ◽

Lightweight Design ◽

Element Model ◽

Optimization Method ◽

Maximum Displacement ◽

Element Analysis ◽

Upper Limb Exoskeleton ◽

Topology Optimization Method

Topology optimization is a widely used lightweight design method for structural design of the collaborative robot. In this article, a topology optimization method for the robot lightweight design is proposed based on finite element analysis of the assembly so as to get the minimized weight and to avoid the stress analysis distortion phenomenon that compared the conventional topology optimization method by adding equivalent confining forces at the analyzed part’s boundary. For this method, the stress and deformation of the robot’s parts are calculated based on the finite element analysis of the assembly model. Then, the structure of the parts is redesigned with the goal of minimized mass and the constraint of maximum displacement of the robot’s end by topology optimization. The proposed method has the advantages of a better lightweight effect compared with the conventional one, which is demonstrated by a simple two-linkage robot lightweight design. Finally, the method is applied on a 5 degree of freedom upper-limb exoskeleton robot for lightweight design. Results show that there is a 10.4% reduction of the mass compared with the conventional method.

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Nonlinear Finite Element Analysis of Unanchored Steel Liquid Storage Tanks Subjected to Seismic Loadings

Volume 8: Seismic Engineering ◽

10.1115/pvp2017-65814 ◽

2017 ◽

Cited By ~ 3

Author(s):

Hoang Nam Phan ◽

Fabrizio Paolacci ◽

Philippe Mongabure

Keyword(s):

Finite Element ◽

Free Surface ◽

Power Plants ◽

Nonlinear Dynamic Analysis ◽

Analysis Procedure ◽

Nonlinear Finite Element ◽

Shaking Table ◽

Storage Tanks ◽

Liquid Storage ◽

Seismic Loadings

Steel liquid storage tanks are widely used in industries and nuclear power plants. Damage in tanks may cause a loss of containment, which could result in serious economic and environmental consequences. For the purpose of the earthquake-resistant design of tanks, it is important to use a rational and reliable nonlinear dynamic analysis procedure. The analysis procedure should be capable of evaluating not only the comprehensive seismic responses but also the damage states of tank components under artificial or real earthquakes. The present paper deals with the nonlinear finite element modeling of steel liquid storage tanks subjected to seismic loadings. A reduce-scale unanchored steel liquid storage tank with the broad configuration from a shaking stable test (i.e., the INDUSE-2-safety project) is selected for this study. The fluid-structure interaction problem of the tank-liquid system is analyzed using the Abaqus software with an explicit time integration approach. In particular, the steel tank is modeled based on a Lagrangian formulation, while an Arbitrary Lagrangian-Eulerian adaptive mesh is used in the liquid domain to permit large deformations of the free surface sloshing. The finite element results in terms of the sloshing of the liquid free surface and the uplift response of the base plate are evaluated and compared with the experimental data that is obtained from the shaking table test for the tank under the INDUSE-2-safety project.

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3D Finite Element Model for Writing Long-Period Fiber Gratings by CO2 Laser Radiation

Sensors ◽

10.3390/s130810333 ◽

2013 ◽

Vol 13 (8) ◽

pp. 10333-10347 ◽

Cited By ~ 6

Author(s):

João Coelho ◽

Marta Nespereira ◽

Manuel Abreu ◽

José Rebordão

Keyword(s):

Finite Element ◽

Laser Radiation ◽

Finite Element Model ◽

Co2 Laser ◽

Element Model ◽

Fiber Gratings ◽

3D Finite Element ◽

Long Period ◽

Long Period Fiber Gratings ◽

Co2 Laser Radiation

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Determination of Material/Geometry of the Section Most Adequate for a Static Loaded Beam Subjected to a Combination of Bending and Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.730-732.507 ◽

2012 ◽

Vol 730-732 ◽

pp. 507-512 ◽

Cited By ~ 3

Author(s):

Hugo Miguel Silva ◽

José Filipe Bizarro de Meireles

Keyword(s):

Finite Element ◽

Material Properties ◽

Model Updating ◽

Material Selection ◽

Young Modulus ◽

Element Model ◽

Mechanical Tests ◽

Correct Operation ◽

Short Period ◽

Relevant Material

The acceleration of industrial machines mobile parts has been increasing over the last few years, due to the need of higher production in a short period of time. The machines were dimensioned for a lower value of acceleration, which means there is not enough rigidity for the correct operation at much higher accelerations. Nowadays, the accelerations can be near 12 times the acceleration of gravity. There is the need of improving rigidity to make possible the correct machine operation without undesired vibrations that can ultimately lead to failure. The main applications of this work are plotters and laser cutting machines. To improve rigidity, one must improve the relevant material properties, and the relevant geometric variables of the model.[1] A novel Finite Element Model Updating methodology is presented in this paper. The considered models were : a ribbed plate and a tubular beam. The models were built by means of the Finite Element Method (FEM), and MATLAB was used to control the optimization process, using a programming code. Both material properties and geometric parameters were optimized. The main aim of the materials modeling is to know how the value of the objective function changes with the value of the material properties. Materials selection was performed, using material selection charts, to select the best material for the application. The value of these properties was not in the catalogue, and the properties used to perform the material selection were related to a material sub-class, Eg. Steel. The final material selection determined the best specific material for the application, and that material was mechanically tested. The mechanical tests performed were: Tensile Test and Extensometry Test, to obtain the relevant material properties, mainly Young Modulus, Poisson Coefficient and Yield Stress. The deflection of the optimized models reduced strongly in comparison to the initial models.

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