• Title, Summary, Keyword: seismic behavior

Search Result 1,667, Processing Time 0.048 seconds

Three-Dimensional Seismic Analysis for Spent Fuel Storage Rack

  • Lee, Gyu-Mahn;Kim, Kang-Soo;Park, Keun-Bae;Park, Jong-Kyun
    • Nuclear Engineering and Technology
    • /
    • v.30 no.2
    • /
    • pp.91-98
    • /
    • 1998
  • Time history analysis is usually performed to characterize the nonlinear seismic behavior of a spent fuel storage rack(SFSR). In the past, the seismic analyses of the SFSR were performed with two-dimensional planar models, which could not account for torsional response and simultaneous multi-directional seismic input In this study, three-dimensional seismic analysis methodology is developed for the single SFSR using the ANSYS code. The 3D- Model can be used to determine the nonlinear behavior of the rack, i.e., sliding, uplifting, and impact evaluation between the fuel assembly and rack, and rack and the pool wall, This paper also reviews the 3-D modeling of the SFSR and the adequacy of the ANSYS for the seismic analysis. AS a result of the adquacy study, the method of ANSYS transient analysis with acceleration time history is suitable for the seismic analysis of highly nonlinear structure such as an SFSR but it isn't appropriate to use displacement time history of seismic input.

  • PDF

A Study of influence factors on the bridge seismic behavior (교량의 지진거동에 미치는 영향인자에 관한 연구)

  • Choi, Jong-Man;Kook, Seung-Kyu;Kim, Jun-Bum;Jung, Dong-Won
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • /
    • pp.372-379
    • /
    • 2005
  • The earthquake resistant design concept allows the nonlinear behavior of structures under the design earthquake. Therefore the response spectrum method provided in most codes introduces the response modification factors to consider the nonlinear behavior in the design process. For bridges, the response modification factors are given according to the ductility as well as the redundancy of piers. In this study, among influence factors on the nonlinear seismic behavior, the randomness of artificial accelerograms simulated with different durations, the pier ductility represented by the inelastic behavior characteristic curve and the regularity represented by pier heights are selected. The influence of such factor on the seismic behavior is investigated by comparing response modification factors calculated with the nonlinear time step analysis.

  • PDF

Experimental study on the deformation characteristics of RC beam-column subassemblages

  • Guo, Zixiong;Yang, Yong
    • Structural Engineering and Mechanics
    • /
    • v.21 no.4
    • /
    • pp.393-406
    • /
    • 2005
  • Cyclic loading tests were carried out on six half-scale reinforced concrete beam-column subassemblages designed to the current Chinese Seismic Design Code for Buildings. The deformation behavior and restoring force characteristics of the subassemblages were studied. Emphasis was directed on their seismic behavior and deformation components. Based on test data and a simplified analysis model of the global and local deformation, the contribution of the deformation components due to beam flexure, column flexure, joint shear, and slippage of longitudinal reinforcement in the joint to the global deformation of subassemblages at different displacement amplitudes of cyclic loading was investigated.

Seismic Behavior Characteristics of Stone Pagoda According to Contact Surface Types (접촉면 처리 방식에 따른 석탑의 내진 특성 평가)

  • Kim, Ho-Soo;Kim, Dong-Kwan;Won, Tae-Ho;Jeon, Geon-Woo
    • Journal of Korean Association for Spatial Structures
    • /
    • v.19 no.3
    • /
    • pp.41-50
    • /
    • 2019
  • The stone pagoda continued to be damaged by weathering and corrosion over time, and natural disasters such as earthquake are accelerating the destruction of cultural properties. Stone pagoda has discontinuous structure behavior and is very vulnerable to the seismic load acting in lateral direction. It is necessary to analyze various design variables as the contact surface characteristics play an important role in the dynamic behavior of stone pagodas. For this purpose, contact surface characteristics of stone pagoda can be classified according to surface roughness and filler type, and representative model is selected and structural modeling and analysis are performed using the discrete element method. Also, the seismic load according to the repetition period is calculated and the dynamic analysis is performed considering the discontinuous characteristics of the stone pagoda. Finally, the seismic behavior characteristics can be analyzed by the evaluation of stresses, displacements and structural safety.

Seismic Performance of Circular Columns considering Transverse Steel Details (횡방향철근 상세에 따른 원형기둥의 내진성능)

  • 이재훈
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • /
    • pp.259-266
    • /
    • 2000
  • This study was conducted to investigate the seismic behavior assessment of circular reinforcement concrete bridge piers particularly with regard to assessing the displacement ductility curvature ductility response modification factor(R) and plastic hinge region etc, The experimental variables of bridge piers test consisted of transverse steel details amount and spacing different axial load levels etc. The test results indicated that reinforcement concrete bridge piers with confinement steel by the code specification exhibited suffcient ductile behavior and seismic performance. Also it is found that current seismic design code specification of confinement steel requirements may be revised.

  • PDF

SEismic Performance of Circular RC Bridge Piers designed in Moderate on low Seismic Zone (중.약진 지역의 원형 내진 RC 교각의 내진성능평가)

  • 박종협;조창백;박희상;정영수
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.452-457
    • /
    • 2000
  • This research aims at evaluating the seismic performance of the existing R/C bridge piers, which were seismically designed in accordance with the provision of moderate confinement design code (Eurocode 8). The work presented in this paper experimentally investigates the ductility and hysteretic behavior of circular reinforced concrete columns with moderate confinement. Pseudo-dynamic tests have been carried out on two scaled R/C column specimens to investigate their hysteretic behavior and other seismic performance.

  • PDF

Seismic Shear Design of Composite Beam-Steel Column Joints (합성보-철골기둥 접합부의 내진전단설계)

  • 이승준
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • /
    • pp.45-51
    • /
    • 1992
  • Trilinear analytical models representing the behavior of composite beam-steel column joints and seismic shear design method for the joints are presented. Emphasis is placed on the effect of the concrete slab on the behavior of the joints. To validate the analytical models, Comparisons with the experimental results are made. Application of the proposed method to seismic shear design of joints improves the seismic resistance of the steel frame with composite slab.

  • PDF

Experimental study on seismic behavior of RC beam-column joints retrofitted using prestressed steel strips

  • Yang, Yong;Chen, Yang;Chen, Zhan;Wang, Niannian;Yu, Yunlong
    • Earthquakes and Structures
    • /
    • v.15 no.5
    • /
    • pp.499-511
    • /
    • 2018
  • This paper aims to investigate the seismic performance of the prestressed steel strips retrofitted RC beam-column joints. Two series of joint specimens were conducted under compression load and reversed cyclic loading through quasi-static tests. Based on the test results, the seismic behavior of the strengthened joints specimens in terms of the failure modes, hysteresis response, bearing capacity, ductility, stiffness degradation, energy dissipation performance and damage level were focused. Moreover, the effects of the amount of the prestressed steel strips and the axial compression ratio on seismic performance of retrofitted specimens were analyzed. It was shown that the prestressed steel strips retrofitting method could significantly improve the seismic behavior of the RC joint because of the large confinement provided by prestressed steel strips in beam-column joints. The decrease of the spacing and the increase of the layer number of the prestressed steel strips could result in a better seismic performance of the retrofitted joint specimens. Moreover, increasing the axial compression ration could enhance the peak load, stiffness and the energy performance of the joint specimens. Furthermore, by comparison with the specimens reinforced with CFRP sheets, the specimens reinforced with prestressed steel strips was slightly better in seismic performance and cost-saving in material and labor. Therefore, this prestressed steel strips retrofitting method is quite helpful to enhance the seismic behavior of the RC beam-column joints with reducing the cost and engineering time.

Seismic Behavior of RC Beam-Column Exterior Joints with Unbonded Tendons and High Strength Concrete (비부착 강연선과 고강도 콘크리트를 적용한 철근콘크리트 외부 접합부의 내진 거동)

  • Kwon, Byung Un;Kang, Thomas H.-K.
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.19 no.6
    • /
    • pp.283-292
    • /
    • 2015
  • In the moment frame subjected to earthquake loads, beam-column joint is structurally important for ductile behavior of a system. ACI Committee 352 proposed guidelines for designing beam-column joint details. The guidelines, however, need to be updated because of the lack of data regarding several factors that may improve the performance of joints. The purpose of this study is to investigate the seismic performance of reinforced concrete exterior joints with high-strength materials and unbonded tendons. Three specimens with different joint shear demand-to-strength ratios were constructed and tested, where headed bars were used to anchor the beam bars into the joint. All specimens showed satisfactory seismic behavior including moment strength of 1.3 times the nominal moment, ductile performance (ductility factor = at least 2.4), and sufficiently large dissipated energy.

Performance-based design of tall buildings for wind load and application of response modification factor

  • Alinejad, Hamidreza;Jeong, Seung Yong;Kang, Thomas H.K.
    • Wind and Structures
    • /
    • v.31 no.2
    • /
    • pp.153-164
    • /
    • 2020
  • In the design of buildings, lateral loading is one of the most important factors considered by structural designers. The concept of performance-based design (PBD) is well developed for seismic load. Whereas, wind design is mainly based on elastic analysis for both serviceability and strength. For tall buildings subject to extreme wind load, inelastic behavior and application of the concept of PBD bear consideration. For seismic design, current practice primarily presumes inelastic behavior of the structure and that energy is dissipated by plastic deformation. However, due to analysis complexity and computational cost, calculations used to predict inelastic behavior are often performed using elastic analysis and a response modification factor (R). Inelastic analysis is optionally performed to check the accuracy of the design. In this paper, a framework for application of an R factor for wind design is proposed. Theoretical background on the application and implementation is provided. Moreover, seismic and wind fatigue issues are explained for the purpose of quantifying the modification factor R for wind design.