• 제목/요약/키워드: Large structures

검색결과 4,671건 처리시간 0.029초

Seismic Design of Structures in Low Seismicity Regions

  • 이동근;조소훈;고현
    • 한국지진공학회논문집
    • /
    • 제11권4호
    • /
    • pp.53-63
    • /
    • 2007
  • Seismic design codes are developed mainly based on the observation of the behavior of structures in the high seismicity regions where structures may experience significant amount of inelastic deformations and major earthquakes may result in structural damages in a vast area. Therefore, seismic loads are reduced in current design codes for building structures using response modification factors which depend on the ductility capacity and overstrength of a structural system. However, structures in low seismicity regions, subjected to a minor earthquake, will behave almost elastically because of the larger overstrength of structures in low seismicity regions such as Korea. Structures in low seismicity regions may have longer periods since they are designed to smaller seismic loads and main target of design will be minor or moderate earthquakes occurring nearby. Ground accelerations recorded at stations near the epicenter may have somewhat different response spectra from those of distant station records. Therefore, it is necessary to verify if the seismic design methods based on high seismicity would he applicable to low seismicity regions. In this study, the adequacy of design spectra, period estimation and response modification factors are discussed for the seismic design in low seismicity regions. The response modification factors are verified based on the ductility and overstrength of building structures estimated from the farce-displacement relationship. For the same response modification factor, the ductility demand in low seismicity regions may be smaller than that of high seismicity regions because the overstrength of structures may be larger in low seismicity regions. The ductility demands in example structures designed to UBC97 for high, moderate and low seismicity regions were compared. Demands of plastic rotation in connections were much lower in low seismicity regions compared to those of high seismicity regions when the structures are designed with the same response modification factor. Therefore, in low seismicity regions, it would be not required to use connection details with large ductility capacity even for structures designed with a large response modification factor.

다중 구조체의 형태를 가지는 우주비행체의 제어설계 (An integrated control and modeling of multi-body space structures)

  • 김진철
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
    • /
    • pp.401-406
    • /
    • 1991
  • An integrated control design and modeling method of multibody space structures is presented as a tool to control an d describe the large rotational motions of the space structures. The structures representeed with three separated substructures have independent control systems but linked with joints interacting the dynamic motions of the substructures. The effect of the structural flexibility to the control performance was analyzed and the simulation results showed that effectiveness of the designed control logic in controlling the motions of the multi-body space structures.

  • PDF

복합적층 쉘구조의 기하학적 비선형해석 (Geometrically Nonlinear Analysis of Laminated Composite Shell Structures)

  • 유승운
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 1997년도 가을 학술발표회 논문집
    • /
    • pp.119-125
    • /
    • 1997
  • The finite element analysis of plate and shell structures has been one of the major research interests for many years because of the technological importance of such structures. Quite often these structures are constructed by laminated composites. This is due to the high specific stiffness and strength of composite structures. The main objective of this paper is to extend the use of an improved degenerated shell element to the large displacement analysis of plates and shells with laminated composites. The total Lagrangian approach has been chosen for the definition of the deformation and the solution to the nonlinear equilibrium equations is obtained by the Newton-Raphson method.

  • PDF