• Title/Summary/Keyword: seismic section

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Performance-Based Seismic Design for High-Rise Buildings in Japan

  • Nakai, Masayoshi;Koshika, Norihide;Kawano, Kenichi;Hirakawa, Kiyoaki;Wada, Akira
    • International Journal of High-Rise Buildings
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    • v.1 no.3
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    • pp.155-167
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    • 2012
  • This paper introduces the outlines of review and approval processes, general criteria and usual practices taken in Japan for the seismic design of high-rise buildings. The structural calculations are based on time-history analyses followed by performance evaluations. This paper also introduces structural design of two high-rise buildings: one is a 100 m high reinforced concrete residential building, and the other is a 300 m high steel building for mixed use.

Hysteretic Behavior of Retrofitted RC Bridge Piers with Lap Spliced Longitudinal Steels (주철근 겹침이음 및 보강된 RC교각의 이력거동)

  • 이대형;정영수;박창규;박진영;송희원
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.121-126
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    • 2003
  • The objective of this research is to evaluate of seismic performance for reinforced concrete bridge piers with lap splices of longitudinal reinforcement steels using predicting of nonlinear hysteric behavior. For the purpose, enhanced analytical trilinear hystretic model has been proposed to simulate the force-displacement hysteretic curve of RC bridge piers under repeated reversal loads. The moment capacity and corresponding curvature in the plastic hinge have been determined, and the enhanced hysteretic behavior model by five different kinds of branches has been proposed for modeling the stiffness variation of RC section under cyclic loading. The strength and stiffness degradation index are introduced to compute the hysteretic curve for various confinement steel ratios, In addition, the modified curvature factor has been introduced to forecast of seismic performance of longitudinal steel lap spliced and retrofitted specimens. The results of this research will be useful to predict of seismic performance for longitudinal steel with lap spliced and its retrofitted specimens.

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Seismic Safety Analysis of Intake Tower with Hollow Inside Section (중공 단면을 갖는 취수탑의 내진 안전성 평가)

  • Bae, Jung-Joo;Kim, Yon-Gon;Lee, Jee-Ho;Han, Sang-Hoon
    • Journal of the Korean Society of Safety
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    • v.24 no.2
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    • pp.55-61
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    • 2009
  • Seismic Safety Analysis of Intake Tower is very important because failure of intake tower may incur huge chaos on the modem society. Recently, there has been growing much concern about earthquake resistance of existing structures. This research demonstrates the dynamic fluid pressure calculation using added mass simulation. The actual safety evaluation has been conducted through not only the static analysis but also the dynamic analysis. According to the analysis results, the vibration incurred by earthquake may induce considerable damage to the hydraulic structure. Therefore, the appropriate design process out of exact calculation is quite necessary.

Evaluation of Seismic Buckling Load for Seismically Isolated KALIMER Reactor Vessel (면진설계된 KALIMER 원자로용기의 지진좌굴 특성평가)

  • 구경회
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1999.10a
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    • pp.220-227
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    • 1999
  • The Purpose of this paper is to evaluate the buckling strength of conceptually designed KALIMER reactor vessel. For evaluation of the buckling load buckling load the design equations and the finite element analysis are used. In finite element method the eigenvalue buckling analysis nonlinear elastic buckling analysis using snap-through buckling method and nonlinear elastic-plastic buckling analysis are carried out. the calculated buckling loads of KALIMER reactor vessel using the finite element method are in well agreement with those of the design equations. From the calculated results of buckling load in KALIMER rector vessel it is shown that the plasticity of vessel materials significantly affects the buckling load but the initial imperfection has little effects, In checking the limits of bucking load of KALIMER reactor vessel using the ASME B & PV Section III. Subsection NH the non-seismic isolation design can not satisfy the buckling limit requirements but the seismic isolation design can sufficiently satisfy the requirements.

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Dynamics Analysis of Concrete Bridges at Expansion Joints Considering Pounding (신축이음부에서 충돌을 고려한 콘크리트 교량의 동적해석)

  • Choi, Suk-Jung;Yoo, Moon-Sig;Jeon, Chan-Ki;Park, Sun-Kyu
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.1
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    • pp.176-187
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    • 2001
  • Most bridges have expansion joints to accommodate thermal expansion and contraction without inducing large forces in the bridges. To evaluate the effects of earthquake-induced at expansion joints of concrete bridges, the first part of this paper deals with a collinear impact between concrete segments, which have the same cross section but different lengths. Especially, impact force, momentum, strain energy and kinetic energy are formulated in mathematically. These results are then used in the second part of this paper to simulate a realistic yet simple analysis of seismic pounding in concrete bridges. Analysis of seismic pounding in idealized concrete bridges is carried out by using a simple lumped-mass model and rationally determined values of the coefficient of restitution and the duration of impact.

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Seismic Performance Evaluation of RC Bridge Piers by Macro Mathematical Model (Macro해석모델에 의한 RC교각의 내진 성능 평가)

  • Lee Dae Hyoung;Park Chang Kyu;Kim Hyun Jun;Chung Young Soo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.207-210
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    • 2005
  • The objective of this research is to evaluate of seismic performance for reinforced concrete bridge piers with lap splices of longitudinal reinforcement steels using predict of nonlinear hysteric behavior. For the purpose, analytical trilinear hysteretic model has been used to simulate the force displacement hysteretic curve of RC bridge piers under repeated reversal loads. The moment capacity and corresponding curvature in the plastic hinge have been determined, and the enhanced hysteretic behavior model by five different kinds of branches has been proposed for modeling the stiffness variation of RC section under cyclic loading. The strength and stiffness degradation index are introduced to compute the hysteretic curve vary confinement steel ratio. In addition, the modified curvature factor has been introduced to forecast of seismic performance of longitudinal steel lap spliced and retrofitted specimens.

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Shake Table Tests for the Evaluation of Seismic Behavior of RC piers (RC 교각의 내진거동 평가를 위한 진동대 실험)

  • Chung, Young-Soo;Shim, Chang-Su;Park, Chang-Kyu;Park, Chang-Young
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.85-88
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    • 2006
  • This paper deals with shaking table tests on RC piers to evaluate the seismic performance under near fault motion. Small scale models were fabricated and axial force was applied by introducing prestress at the centroid of the column section. Mass effect of the superstructures was simulated by mass frame which was linked with a pier model by steel bars because of the limited payload of shaking table. Friction of the mass frame when it moves was minimized by special details and it was proved before tests. Scale factor of the RC piers was 4.25. Main parameters of the test were details of reinforcements. After verifying the results of shaking table tests, seismic performance was evaluated by increasing the acceleration of the near fault motion.

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An Experimental Study on Seismic Performance of RC Bridge Columns with Oblong Section (원장방형 철근콘크리트 교각의 내진성능에 관한 실험적 연구)

  • 이재훈;고성현;서진원;이지영;한상엽
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.09a
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    • pp.368-375
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    • 2003
  • The objectives of this study were to provide experimental data on the behavior of interlocking spiral columns under cyclic loading, to compare the performance of columns with interlocking spirals to columns with U-type hoops with hook, to study the flexural detailing of interlocking spirals and other transverse steel configurations as the transverse reinforcement The oblong columns with interlocking spirals and with hooked U-type hoops and cross-ties better seismic performance than the rectangular columns with rectangular hoops and cross-ties. The oblong columns with hooked U-type hoops and cross-ties showed better seismic performance than the rectangular columns with rectangular hoops and cross-ties. And this research were to make recommendations for the design of bridge columns incorporating interlocking spirals and U-type hoops with hook as the transverse reinforcement.

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Cyclic load testing and numerical modeling of concrete columns with substandard seismic details

  • Marefat, Mohammad S.;Khanmohammadi, Mohammad;Bahrani, Mohammad K.;Goli, Ali
    • Computers and Concrete
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    • v.2 no.5
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    • pp.367-380
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    • 2005
  • Recent earthquakes have shown that many of existing buildings in Iran sustain heavy damage due to defective seismic details. To assess vulnerability of one common type of buildings, which consists of low rise framed concrete structures, three defective and three standard columns have been tested under reversed cyclic load. The substandard specimens suffered in average 37% loss of strength and 45% loss of energy dissipation capacity relative to standard specimens, and this was mainly due to less lateral and longitudinal reinforcement and insufficient sectional dimensions. A relationship has been developed to introduce variation of plastic length under increasing displacement amplitude. At ultimate state, the length of plastic hinge is almost equal to full depth of section. Using calibrated hysteresis models, the response of different specimens under two earthquakes has been analyzed. The analysis indicated that the ratio between displacement demand and capacity of standard specimens is about unity and that of deficient ones is about 1.7.

Monotonic Loading Tests on Seismic Stiffeners for Vertical Hangers (수직 행거 내진설계용 스티프너의 단조 압축 실험)

  • Chang-Soo Oh;Ha-Sung Kong
    • Journal of the Korea Safety Management & Science
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    • v.25 no.2
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    • pp.187-192
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    • 2023
  • In piping systems, trapeze hangers are subjected to vertical and horizontal seismic loads and stiffeners are used. In this study, monotonic compression tests were conducted with the removable stiffeners using three variables: stiffener clamp fixing position, section length, and installation direction. The maximum load reinforced with stiffeners could withstand a compressive load of 11kN by applying a safety factor of 10%. It could be estimated that the fixing clamp spacing or the length of shape and load had a proportional relationship. And the stiffener must be fixed in the direction of the strong axis on hinge parts. Also the stiffener buckiling load design proposes to use a method of calculate the flexural buckling compressive strength of and unreinforced full threaded bolt.