• Title/Summary/Keyword: seismic displacement

Search Result 1,422, Processing Time 0.026 seconds

Seismic Performance Evaluation of bridge using DCM and CSM (변위계수법과 역량스펙트럼 방법을 이용한 교량의 내진성능 평가)

  • Nam Wang-Hyun;Song Jong-Keol;Chung Yeong-Hwa
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2006.04a
    • /
    • pp.1017-1024
    • /
    • 2006
  • Capacity spectrum method(CSM) of ATC-40(1996) and displacement coefficient method(DCM) of FEMA-273(1997) are applied to evaluate the seismic performance of bridges. In this study, equivalent response is obtained from nonlinear static analysis for the 3spans continues bridge and nonlinear maximum displacement response is calculated using CSM and DCM. Nonlinear maximum displacement response of DCM is larger than this of CSM. It is method that DCM can evaluate target displacement and ductility of structural to be easy and simple, but tend to overestimate the maximum displacement response. Therefore, this method is mainly used at preparation design level to evaluate the structural response. It is not desirable to evaluate the seismic performance using DCM.

  • PDF

Seismic Performance Evaluation of Multi-Span Bridges using CSM and modified DCM (역량스펙트럼 방법과 수정변위계수법을 이용한 다경간 교량의 내진성능 평가)

  • Nam, Wang-Hyun;Song, Jong-Keol;Chung, Yeong-Hwa
    • Journal of Industrial Technology
    • /
    • v.26 no.B
    • /
    • pp.119-126
    • /
    • 2006
  • Capacity spectrum method(CSM) of ATC-40(1996) and displacement coefficient method(DCM)of FEMA-273(1997) are applied to evaluate the seismic performance of bridges. In this study, equivalent response is obtained from nonlinear static analysis for the 3spans continues bridge and nonlinear maximum displacement response is calculated using CSM and DCM. Nonlinear maximum displacement response of DCM is larger than this of CSM. It is method that DCM can evaluate target displacement and ductility of structural to be easy and simple, but tend to overestimate the maximum displacement response. Therefore, this method is mainly used at preparation design level to evaluate the structural response. It is not desirable to evaluate the seismic performance using DCM.

  • PDF

Seismic Response Evaluation of Mid-Story Isolation System According to the Change of Characteristics of the Seismic Isolation Device (면진장치 특성 변화에 따른 중간층 면진시스템의 지진응답 평가)

  • Kim, Hyun-Su;Kim, Su-Geun;Kang, Joo-Won
    • Journal of Korean Association for Spatial Structures
    • /
    • v.18 no.1
    • /
    • pp.109-116
    • /
    • 2018
  • As the number of high-rise buildings increases, a mid-story isolation system has been proposed for high-rise buildings. Due to structural problems, an appropriate isolation layer displacement is required for an isolation system. In this study, the mid-story isolation system was designed and the seismic response of the structure was investigated by varying the yield strength and the horizontal stiffness of the seismic isolation system. To do this, a model with an isolation layer at the bottom of $15^{th}$ floor of a 20-story building was used as an example structure. Kobe(1995) and Nihonkai-Chubu(1983) earthquake are used as earthquake excitations. The yield strength and the horizontal stiffness of the seismic isolation system were varied to determine the seismic displacement and the story drift ratio of the structure. Based on the analytical results, as the yield strength and horizontal stiffness increase, the displacement of the isolation layer decreases. The story drift ratio decreases and then increases. The displacement of the isolation layer and the story drift ratio are inversely proportional. Increasing the displacement of the isolation layer to reduce the story drift ratio can cause the structure to become unstable. Therefore, an engineer should choose the appropriate yield strength and horizontal stiffness in consideration of the safety and efficiency of the structure when a mid-story isolation system for a high-rise building is designed.

Application of MR damper for Vibration Control of Adjacent Buildings (인접건축물의 진동제어를 위한 MR감쇠기의 적용)

  • Kim, Gee-Cheol;Kang, Joo-Won
    • Journal of Korean Association for Spatial Structures
    • /
    • v.12 no.4
    • /
    • pp.99-108
    • /
    • 2012
  • In recently, sky-bridge are often applied to high-rised adjacent buildings for pedestrian bridge. the seisnic response control of adjacent buildings have been studied and magneto-rheological(MR) fluid dampers have been applied to seismic response control. In this study, vibration control effect of the MR damper connected adjacent buildings has been investigated. Adjacent building structures with different natural frequencies were used as example structures. Two typed of control methods, displacement based or velocity based, are applied to determinate control force of MR damper. In this numerical analysis, it has been shown that displacement-based control algorithm is more effective than velocity-based control algorithm for seismic response control of adjacent buildings. And, when displacement-based control method is applied to control of adjacent buildings, the control of building occurred large displacement is more efficient in reducing the seismic response.

Inelastic displacement-based design approach of R/C building structures in seismic regions

  • Rubinstein, Marcelo;Moller, Oscar;Giuliano, Alejandro
    • Structural Engineering and Mechanics
    • /
    • v.12 no.6
    • /
    • pp.573-594
    • /
    • 2001
  • A two-level displacement-based design procedure is developed. To obtain the displacement demands, elastic spectra for occasional earthquakes and inelastic spectra for rare earthquakes are used. Minimum global stiffness and strength to be supplied to the structure are based on specified maximum permissible drift limits and on the condition that the structure responds within the elastic range for occasional earthquakes. The performance of the structure may be assessed by an inelastic push-over analysis to the required displacement and the evaluation of damage indices. The approach is applied to the design of a five-story reinforced concrete coupled wall structure located in the most hazardous seismic region of Argentina. The inelastic dynamic response of the structure subjected to real and artificially generated acceleration time histories is also analyzed. Finally, advantages and limitations of the proposed procedure from the conceptual point of view and practical application are discussed.

Seismic Capacity Evaluation of Bridge Structure using Capacity Spectrum Method (역량스펙트럼법에 의한 교량 구조물의 내진성능평가)

  • 박연수;오백만;박철웅;서병철
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.7 no.5
    • /
    • pp.67-73
    • /
    • 2003
  • The present seismic analysis of Road-Bridge Design Standard is on a basis of load-based analysis which lets structures have the strength over load. In this study, the capacity spectrum method, a kind of displacement based method, which is evaluated by displacement of structure, is presented as an alternative to the analysis method based on load. Seismic capacity is performed about the existing reinforced concrete pier which has already secured seismic design by capacity spectrum method. As a result. capacity spectrum method could realistically evaluate the non-elastic behavior of structures easily and quickly and the displacement of structures for variable ground motion level. And it could efficiently apply to an evaluation of seismic capacity about the existing structure and a verification of design for capacity target of the new structure.

Seismic performance and design method of PRC coupling beam-hybrid coupled shear wall system

  • Tian, Jianbo;Wang, Youchun;Jian, Zheng;Li, Shen;Liu, Yunhe
    • Earthquakes and Structures
    • /
    • v.16 no.1
    • /
    • pp.83-96
    • /
    • 2019
  • The seismic behavior of PRC coupling beam-hybrid coupled shear wall system is analyzed by using the finite element software ABAQUS. The stress distribution of steel plate, reinforcing bar in coupling beam, reinforcing bar in slab and concrete is investigated. Meanwhile, the plastic hinges developing law of this hybrid coupled shear wall system is also studied. Further, the effect of coupling ratio, section dimensions of coupling beam, aspect ratio of single shear wall, total height of structure and the role of slab on the seismic behavior of the new structural system. A fitting formula of plate characteristic values for PRC coupling beams based on different displacement requirements is proposed through the experimental date regression analysis of PRC coupling beams at home and abroad. The seismic behavior control method for PRC coupling beam-hybrid coupled shear wall system is proposed based on the continuous connection method and through controlling the coupling ratio, the roof displacement, story drift angle of hybrid coupled shear wall system, displacement ductility of coupling beam.

Analysis of Behavior of Agricultural Reservoir with Combined Load by 3-D Numerical Analysis (3차원 수치해석을 통한 복합하중이 작용하는 농업용저수지의 거동 분석)

  • Song, Chang Seob;Woo, jea keun;Ahn, kwangkuk;Kim, Myeong Hwan
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.60 no.1
    • /
    • pp.59-65
    • /
    • 2018
  • The object of this paper was to analyze combined load acting on agricultural reservoir. This study was carried out to 3-D numerical modeling for displacement characteristic and seismic acceleration characteristic. The results of study were analyzed and summarized as follow. It was found that the displacement caused by combined load acting on railway and agricultural reservoir did not reflect the effect of load and the seismic wave consistently. The ground accelerations that occur in railway and dam were amplified because 3-D numerical analysis program interprets ground as an elastic body. Actual ground shows characteristics of elasticity and plasticity, so measured values will show different tendency. As a result of analyzing displacement characteristics, it is considered to be related to stiffness. The Ofunato seismic wave, the displacement (77.1 mm) of the body satisfied the allowable displacement (220 mm), but The Hachinohe seismic wave (282.8 mm) did not. It is considered that displacement caused by combined load is affected not only by acceleration but also by characteristics of materials.

Development of the Modified Seismic Coefficient Method to Establish Seismic Design Criteria of Buried Box Structures. (BOX 형 지하구조물의 내진설계 기준 확립을 위한 해석기법개발)

  • 박성우
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2000.04a
    • /
    • pp.194-201
    • /
    • 2000
  • In this study the modified seismic coefficient method for seismic analysis of buried box structures is developed for practical purpose. The loading coefficient in the modified seismic coefficient method is determined from the results of the response displacement analysis. In the developed method adequate velocity response spectrum in accordance with soil condition is also needed to seismic design of buried box structures, In order to investigate applicability of the modified seismic coefficient method various analyses are performed with different parameters such as depth of base rock height and width of box buried depth and value of standard penetration test. Results from the modified seismic coefficient method are compared with those of the response displacement method in terms of the maximum bending moment and the location of it. From the comparison it is shown that the feasibility of the modified seismic coefficient method for seismic analysis of buried box structures.

  • PDF

Seismic Responses of Seismically Isolated Nuclear Power Plant Structure Considering Post-Yield Stiffness of EQS Bearing (EQS 면진장치의 항복 후 강성을 고려한 면진 원전구조물의 지진응답)

  • Kim, Byeong-Su;Song, Jong-Keol
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.20 no.5
    • /
    • pp.319-329
    • /
    • 2016
  • The Eradi Quake System (EQS) is a seismic isolation bearing system designed to minimize forces and displacements experienced by structures subjected to ground motion. The EQS dissipates seismic energy through friction of Poly Tetra Fluoro Ethylene (PTFE) disk pad. In general, a force-displacement relationship of EQS has post yield stiffness hardening during large inelastic displacement. In this study, seismic responses of seismically isolated nuclear power plant (NPP) subjected to design basis earthquake (DBE) and beyond design basis earthquakes (150% DBE and 167% DBE) are compared considering the post yield stiffness hardening effect of EQS. From the results, it can be observed that if the post-yield stiffness hardening effect of EQS is increased, the displacement response of EQS is reduced, and the acceleration and shear responses of containment structures of NPP is increased.