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1

Bond behavior of corroded reinforcements in concrete: an experimental study and hysteresis model

Zhang Yi‑Bo, Zheng Shan-Suo, Dong Li-Guo, Zheng Yue

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

ar. no. e95, 2023

EN

In order to study the effect of both longitudinal reinforcement and stirrups corrosion on the bond performances at steel-concrete interface under reversed cyclic loading, in this paper, the eccentric pull-out tests under reversed cyclic loading were carried out on reinforced concrete (RC) specimens with five corrosion degrees, three concrete cover thicknesses, and three stirrup spacings. The influence of the corrosion rate of longitudinal reinforcement, corrosion rate of stirrups, cover thickness, and stirrup spacing on bond performance indicators was examined, including the initial bond stiffness, peak bond stress, slip at peak bond stress, bond strength at unloading, unloading stiffness, frictional bond resistance, and cumulative energy dissipation. Moreover, the effects of coupling corrosion on cover cracking morphology and bond degradation mechanism were also analyzed. Results indicated that after severe corrosion of longitudinal reinforcement and stirrups, the cover appears cracking or local spalling, and the bond performances are signifcantly reduced. It was also showed that thickening cover or densifying stirrups could improve the interface bond performance and energy dissipation capacity. Each hysteresis parameter degrades apparently under the controlling slip corresponding to the peak bond stress. Subsequently, based on the analysis results and previous studies, empirical local bond stress-slip hysteresis models for corroded longitudinal reinforcement and corroded stirrup under reversed cyclic loading were proposed. Good consistency was observed for the hysteresis model with existing experimental data.

2

Autonomous implicit models of pinched hystereses with application to memristors

Marszalek W.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 4

13--16

EN

This paper analyzes systems with an autonomous dynamics equivalent to that of mem-inductors and mem-capacitors. The systems have oscillatory inductive and capacitive pinched self-crossing hystereses that follow the folded saddle dynamics around the origin and two equilibria of the center type, each located on the opposite sides of singularity (impasse curve). When parameters of the systems change to yield an increased frequency of oscillations, then the areas enclosed by the hystereses decrease. The time zero-crossing property of the systems is also discussed.

PL

W artykule dokonano analizy dynamiki pewnej klasy układów autonomcznych. Rozważane układy charakteryzują się indukcyjnymi i pojemnościowymi, ścisniętymi i przecinającymi się histerezami, powstajacymi w dynamice siodła na fałdzie wraz z dwoma punktami równowagi typu centrum, położonymi po przeciwnych stronach krzywej osobliwej z punktami impasowymi. Wraz ze zmianą parametrów prowadzącą do zwiększenia częstotliwosci oscylacji obszar objęty histerezą zmniejsza się . Własność jednoczesnego zerowania się sygnałów w czasie jest rownież rozważana.

3

Wykorzystanie strategii ewolucyjnej do estymacji parametrów modelu histerez

Chwastek K., Dudek G.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 12b

5-7

PL

Zaproponowano strategię ewolucyjną do estymacji parametrów fenomenologicznego modelu histerezy autorstwa Takácsa uzupełnionego o składnik reprezentujący procesy odwracalne zachodzące podczas procesu magnesowania. …

EN

An evolution strategy for parameter estimation of the Takács phenomenological model of hysteresis is proposed. The description is supplemented with a component related to reversible magnetization processes.

4

Analysis of Vibration Stability of Oscillators with Hysteresis

Awrejcewicz J., Dzyubak L.

Vibrations in Physical Systems

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2004

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Vol. 21

63--66