• Title, Summary, Keyword: hysteretic model

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Effect of hysteretic constitutive models on elasto-plastic seismic performance evaluation of steel arch bridges

  • Wang, Tong;Xie, Xu;Shen, Chi;Tang, Zhanzhan
    • Earthquakes and Structures
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    • v.10 no.5
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    • pp.1089-1109
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    • 2016
  • Modified two-surface model (M2SM) is one of the steel elasto-plastic hysteretic constitutive models that consider both analysis accuracy and efficiency. However, when M2SM is used for complex strain history, sometimes the results are irrational due to the limitation of stress-strain path judgment. In this paper, the defect of M2SM was re-modified by improving the judgment of stress-strain paths. The accuracy and applicability of the improved method were verified on both material and structural level. Based on this improvement, the nonlinear time-history analysis was carried out for a deck-through steel arch bridge with a 200 m-long span under the ground motions of Chi-Chi earthquake and Niigata earthquake. In the analysis, we compared the results obtained by hysteretic constitutive models of improved two-surface model (I2SM) presented in this paper, M2SM and the bilinear kinematic hardening model (BKHM). Results show that, although the analysis precision of displacement response of different steel hysteretic models differs little from each other, the stress-strain responses of the structure are affected by steel hysteretic models apparently. The difference between the stress-strain responses obtained by I2SM and M2SM cannot be neglected. In significantly damaged areas, BKHM gives smaller stress result and obviously different strain response compared with I2SM and M2SM, and tends to overestimate the effect of hysteretic energy dissipation. Moreover, at some position with severe damage, BKHM may underestimate the size of seismic damaged areas. Different steel hysteretic models also have influences on structural damage evaluation results based on deformation behavior and low cycle fatigue, and may lead to completely different judgment of failure, especially in severely damaged areas.

Nonlinear hysteretic behavior of hybrid beams consisted of reinforced concrete and steel (철근콘크리트와 철골조로 이루어진 혼합구조보의 비선형 이력거동에 관한 연구)

  • 이은진;김욱종;문정호;이리형
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • pp.19-26
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    • 1999
  • This paper describes an analytical study on nonlinear hysteretic behavior of hybrid steel beam with reinforced concrete ends. Two types of analytical model, Polygonal Model[PM] and Hybrid Model[HM], were used to represent the nonlinear hysteretic behavior PM used three parameters, HM used an additional parameter to consider the initial stiffness reduction. The parameters calibrated comparing the hysteretic performance obtained from experiments. The purpose of this study is to develop an analytical model which can take into account the initial stiffness reduction of the hybrid members and to represent exactly the hysteretic performance for the hybrid structures with RC and steel. The analytical study showed PM tends to overestimate initial stiffness and strength. However, HM which is capable to consider the initial stiffness reduction gave good prediction on initial stiffness, post-yielding performance, strength, pinching response and so on.

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Reduction of the Seismetic rRspocses by Using the Modified Hysteretic Bi-Linear Model of the Seismic Isolator (수정히스테리틱 Bi-Linear 면진베어린 모델을 사용한 지진응답감소)

  • Koo, G.H.;Lee, J.H.;Kim, J.B.;Lee, H.Y.;Yoo, B.
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.1
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    • pp.127-134
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    • 1996
  • In general, seismic isolators which are made of laminated rubber and shim plate have characteristics of complex hysteretic behavior. When shear deformation of the seismic isolator is small, the isolator hassimple hysteretic almost bi-linear behabior. But on large shear deformation hardening effects may occur. This paper proposes a moldeling method of the seimic isolator with modified hysteretic bi-linear model which can consider the hardening effects. From the results of the seismic analyses of the isolated system it is shown that the responses are singificantly reduced compared with those of the non-isolated system. The modified hysteretic bi-linear model of the isolator gives larger ZPA(zero period acceleration) than those of the simple hysteretic bi-linear model and the equivalunt spring-damper model.

Energy-Based Hysteretic Models for R/C Members (에너지 소산능력에 기초한 철근콘크리트 부재의 이력모델)

  • Eom, Tae-Sung;Park, Hong-Gun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.5
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    • pp.45-54
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    • 2004
  • Since existing hysteretic models for R/C members focused on presenting the degrading stiffness using empirical equations based on experiments, they cannot accurately predict the energy dissipation capacity during cyclic loading. Recently, design equations which can evaluate the energy dissipation capacity of R/C members were developed. Based on those equations, in the present study, an energy-based hysteretic model for flexure-dominated R/C members was developed. The proposed model was devised to dissipate the same energy as the actual one dissipated during a complete load cycle. The proposed model represents the hysteretic behaviors of R/C members accompanied by stiffness degradation and pinching using primary and cyclic curves and six unloading/reloading rules. The proposed model was verified by comparisons with various experimental results. The energy-based hysteretic model can be used to develop computer programs for static and dynamic analysis/design because it is simple and easily applicable to numerical analysis.

Analytic Hysteretic Model of Reinforced Concrete Members (철근콘크리트 부재의 해석적 이력모델)

  • 정영수
    • Computational Structural Engineering
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    • v.4 no.1
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    • pp.133-142
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    • 1991
  • A mathematical hysteretic model has been developed to analytically reproduce the experimental hysteretic behavior of reinforced concrete members. This mode[2, 3] can simulate the nonlinear response of reinforced concrete members with sufficient accuacy, which are characterized by following important hysteretic behaviors: stiffness degradation, strength deterioration and shear effect. In order to illustrate the capabilities of the proposed mathematical model, numerical examples are presented with the reproduction of experimental hysteretic behavior of RC members and frames.

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A neural network model to assess the hysteretic energy demand in steel moment resisting frames

  • Akbas, Bulent
    • Structural Engineering and Mechanics
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    • v.23 no.2
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    • pp.177-193
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    • 2006
  • Determining the hysteretic energy demand and dissipation capacity and level of damage of the structure to a predefined earthquake ground motion is a highly non-linear problem and is one of the questions involved in predicting the structure's response for low-performance levels (life safe, near collapse, collapse) in performance-based earthquake resistant design. Neural Network (NN) analysis offers an alternative approach for investigation of non-linear relationships in engineering problems. The results of NN yield a more realistic and accurate prediction. A NN model can help the engineer to predict the seismic performance of the structure and to design the structural elements, even when there is not adequate information at the early stages of the design process. The principal aim of this study is to develop and test multi-layered feedforward NNs trained with the back-propagation algorithm to model the non-linear relationship between the structural and ground motion parameters and the hysteretic energy demand in steel moment resisting frames. The approach adapted in this study was shown to be capable of providing accurate estimates of hysteretic energy demand by using the six design parameters.

Estimation of Hysteretic Interfacial Stiffness of Contact Surfaces

  • Kim, Nohyu
    • Journal of the Korean Society for Nondestructive Testing
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    • v.33 no.3
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    • pp.276-282
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    • 2013
  • This paper proposes an ultrasonic method for measurement of linear and hysteretic interfacial stiffness of contacting surfaces between two steel plates subjected to nominal compression pressure. Interfacial stiffness was evaluated by the reflection and transmission coefficients obtained from three consecutive reflection waves from solid-solid surface using the shear wave. A nonlinear hysteretic spring model was proposed and used to define the quantitative interfacial stiffness of interface with the reflection and transmission coefficients. Acoustic model for 1-D wave propagation across interfaces is developed to formulate the reflection and transmission waves and to determine the linear and nonlinear hysteretic interfacial stiffness. Two identical plates are put together to form a contacting surface and pressed by bolt-fastening to measure interfacial stiffness at different states of contact pressure. It is found from experiment that the linear and hysteretic interfacial stiffness are successfully determined by the reflection and transmission coefficient at the contact surfaces through ultrasonic pulse-echo measurement.

A new practical equivalent linear model for estimating seismic hysteretic energy demand of bilinear systems

  • Samimifar, Maryam;Massumi, Ali;Moghadam, Abdolreza S.
    • Structural Engineering and Mechanics
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    • v.70 no.3
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    • pp.289-301
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    • 2019
  • Hysteretic energy is defined as energy dissipated through inelastic deformations during a ground motion by the system. It includes frequency content and duration of ground motion as two remarkable parameters, while these characteristics are not seen in displacement spectrum. Since maximum displacement individually cannot be the appropriate criterion for damage assessment, hysteretic energy has been evaluated in this research as a more comprehensive seismic demand parameter. An innovative methodology has been proposed to establish a new equivalent linear model to estimate hysteretic energy spectrum for bilinear SDOF models under two different sets of earthquake excitations. Error minimization has been defined in the space of equivalent linearization concept, which resulted in equivalent damping and equivalent period as representative parameters of the linear model. Nonlinear regression analysis was carried out for predicting these equivalent parameter as a function of ductility. The results also indicate differences between seismic demand characteristics of far-field and near-field ground motions, which are not identified by most of previous equations presented for predicting seismic energy. The main advantage of the proposed model is its independency on parameters related to earthquake and response characteristics, which has led to more efficiency as well as simplicity. The capability of providing a practical energy based seismic performance evaluation is another outstanding feature of the proposed model.

Flutter Control of a Lifting Surface via Visco-Hysteretic Vibration Absorbers

  • Lacarbonara, Walter;Cetraro, Marek
    • International Journal of Aeronautical and Space Sciences
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    • v.12 no.4
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    • pp.331-345
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    • 2011
  • In this paper, a visco-hysteretic vibration absorber (VA) is proposed to increase the flutter speed of an airfoil and enhance damping in the pre- and post-flutter regimes. The passive system consists of a parallel arrangement of a dashpot and a rateindependent hysteretic element, represented by the Bouc-Wen differential model. The equations of motion are obtained and various tools of linear and nonlinear dynamics are employed to study the effects of the visco-hysteretic VA in the pre- and postflutter ranges.

A Flexible Multi-body Dynamic Model for Analyzing the Hysteretic Characteristics and the Dynamic Stress of a Taper Leaf Spring

  • Moon Il-Dong;Yoon Ho-Sang;Oh Chae-Youn
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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    • pp.1638-1645
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    • 2006
  • This paper proposes a modeling technique which is able to not only reliably and easily represent the hysteretic characteristics but also analyze the dynamic stress of a taper leaf spring. The flexible multi-body dynamic model of the taper leaf spring is developed by interfacing the finite element model and computation model of the taper leaf spring. Rigid dummy parts are attached at the places where a finite element leaf model is in contact with an adjacent one in order to apply contact model. Friction is defined in the contact model to represent the hysteretic phenomenon of the taper leaf spring. The test of the taper leaf spring is conducted for the validation of the reliability of the flexible multi-body dynamic model of the taper leaf spring developed in this paper. The test is started at an unloaded state with the excitation amplitude of $1{\sim}2mm/sec$ and frequency of 132 mm. First, the simulation is conducted with the same condition as the test. Then, the simulations are conducted with various amplitudes in a loaded state. The hysteretic diagram from the test is compared with the ones from the simulation for the validation of the reliability of the model. The dynamic stress analysis of the taper leaf spring is also conducted with the developed flexible multi-body dynamic model under a dynamic loading condition.