Analytical Model for the Hysteretic Behavior of SRC Columns

To simulate the hysteretic behavior and propose the analytical model of steel reinforced concrete (SRC) columns under low cyclic loads, different fiber models which can reflect the mechanical behavior of materials are used in this paper. The unconfined concrete, partially confined concrete, highly confined concrete, structure steel and longitudinal reinforcement bars of the complex cross section can be established by OpenSees program which can define the different fibers for kinds of materials with their own stress-strain relations, respectively. Based on fiber models, the analytical model for simulating the hysteretic behavior of SRC columns is proposed. By comparing with the conventional simulation results, the results which are obtained from the proposed analytical model in this paper agree with the experimental results better.

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Experimental and Numerical Study of Mechanical Behavior of Welded Steel Plate Joints

Metals ◽

10.3390/met10101293 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1293

Author(s):

Hongwei Ma ◽

Hao Zheng ◽

Wei Zhang ◽

Zhanzhan Tang ◽

Eric M. Lui

Keyword(s):

Mechanical Behavior ◽

Failure Modes ◽

Steel Plate ◽

Numerical Study ◽

Damage Model ◽

Hysteretic Behavior ◽

Cyclic Loads ◽

Welded Steel ◽

Damage Process ◽

Monotonic Loads

This paper describes a study of welded steel plate joints using experimental and numerical methods. The objectives of this study are to observe the mechanical behavior of welded plate joints under monotonic and cyclic loads, identify their damage degradation processes, and provide useful test data for future damage analysis of beam-column connections in steel frame structures. Six specimens were designed, of which three were tested under monotonic loads, and the other three were tested under cyclic loads. The test setup consisted of three plates arranged in a cruciform and connected by two groove welds. The monotonic and cyclic loads were applied to the free end of the two outstanding plates, inducing a pulling force on the welded joint. Because the only element studied in the present work is the weld, the sizes of the three plates were kept constant. The responses of these welded plate joints are discussed in terms of their experimentally and numerically obtained mechanical parameters, hysteretic behavior, strain variations, stiffness degradation, damage process, and failure modes. The results show that the energy damage model outperforms the displacement damage model in terms of indicating the degree of damage. Furthermore, if designed according to code, all these welded plate joints perform satisfactorily.

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Behavior of Reinforced Concrete Columns with ‘T’-Shaped Cross Section after Exposure to Fire

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.1696 ◽

2011 ◽

Vol 250-253 ◽

pp. 1696-1701 ◽

Cited By ~ 1

Author(s):

Yu Ye Xu ◽

Bo Wu ◽

Rong Hui Wang ◽

Ming Jiang

Keyword(s):

Reinforced Concrete ◽

Yield Strength ◽

Cross Section ◽

Residual Strength ◽

Effective Length ◽

Longitudinal Reinforcement ◽

Eccentricity Ratio ◽

Rc Columns ◽

Simulation Results ◽

Shaped Cross Section

The residual strength of reinforced concrete (RC) columns with ‘T’-shaped cross section after fire are decreased more quickly than those of RC columns with rectangular cross section for the former have thinner sectional thickness and larger surface area. The influence of several main parameters, such as exposure times, effective lengths, sectional dimensions, load eccentricity ratios, reinforcement ratios, load angles and longitudinal reinforcement yield strength on the residual strength of RC columns with ‘T’-shaped cross section after exposure to fire was investigated. A self-developed finite element program CAFIRE was applied in this study. 24300 hypothetical cases of columns after subjected to fire on all sides were selected for residual strength analysis. Different fire exposure times, effective lengths, cross section dimensions, load eccentricity ratios, reinforcement ratios, load angles and longitudinal reinforcement yield strength were considered in the analyses. Based on the simulation results, a practical method was proposed for calculating the residual strength of columns with ‘T’-shaped cross section after subjected to fire on all sides. The simulation results indicate that: (a) the residual strength of columns with ‘T’-shaped cross section decreases linearly with the increase of effective length, but it increases linearly with sectional width, ratio of sectional height to sectional width, and yield strength of longitudinal reinforcement strength; (b) the residual strength of ‘T’-shaped columns decreases markedly for a load eccentricity ratio in the range of 0.0 to 1.0, whereas it varies slightly for a load eccentricity ratio between 1.0 and 3.0.

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Nanodevices Tend to Be Round

Micromachines ◽

10.3390/mi12030330 ◽

2021 ◽

Vol 12 (3) ◽

pp. 330

Author(s):

Georges Pananakakis ◽

Gérard Ghibaudo ◽

Sorin Cristoloveanu

Keyword(s):

Diffusion Process ◽

Thermal Diffusion ◽

Cross Section ◽

Gate Voltage ◽

Supportive Evidence ◽

Inversion Mode ◽

Nanowire Transistor ◽

Junctionless Transistor ◽

Simulation Results ◽

Thermal Diffusion Process

Under several circumstances, a nanowire transistor with a square cross-section behaves as a circular. Taking the Gate-All-Around junctionless transistor as a primary example, we investigate the transition of the conductive region from square to circle-like. In this case, the metamorphosis is accentuated by smaller size, lower doping, and higher gate voltage. After defining the geometrical criterion for square-to-circle shift, simulation results are used to document the main consequences. This transition occurs naturally in nanowires thinner than 50 nm. The results are rather universal, and supportive evidence is gathered from inversion-mode Gate-All-Around (GAA) MOSFETs as well as from thermal diffusion process.

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Cheating at Craps

ACM SIGMETRICS Performance Evaluation Review ◽

10.1145/3466826.3466845 ◽

2021 ◽

Vol 48 (4) ◽

pp. 53-61

Author(s):

Andrea Marin ◽

Carey Williamson

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Modeling And Simulation ◽

Analytical Model ◽

Quantitative Evaluation ◽

Mathematical Analysis ◽

Simulation Modeling ◽

Analytical Modeling ◽

The World ◽

Simulation Results

Craps is a simple dice game that is popular in casinos around the world. While the rules for Craps, and its mathematical analysis, are reasonably straightforward, this paper instead focuses on the best ways to cheat at Craps, by using loaded (biased) dice. We use both analytical modeling and simulation modeling to study this intriguing dice game. Our modeling results show that biasing a die away from the value 1 or towards the value 5 lead to the best (and least detectable) cheating strategies, and that modest bias on two loaded dice can increase the winning probability above 50%. Our Monte Carlo simulation results provide validation for our analytical model, and also facilitate the quantitative evaluation of other scenarios, such as heterogeneous or correlated dice.

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