• 제목/요약/키워드: connection rigidity

검색결과 66건 처리시간 0.024초

DNA 크로스오버가 오리가미 구조물의 강도에 미치는 영향에 대한 유한요소법 기반 민감도 분석

  • 김경수
    • EDISON SW 활용 경진대회 논문집
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    • 제5회(2016년)
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    • pp.269-269
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    • 2016
  • DNA origami is the most fitting nano-technology for synthesis of complex nano-structures. DNA crossover which ties DNA helices together are the main reason for the stable sustenance of origami structures with respect to other nano-scale structures. The mechanical properties of DNA crossovers have profound connection with structural rigidity, and it is a known fact that the rigidity changes depending on the arrangement of crossovers. It is possible to control the rigidity of origami structures for functionality and furthermore extends the field of DNA origami application. Here, we investigate the effect of crossovers on 2-Dimensional DNA structures varying crossover arrangement by sensitivity analysis based on finite element model. The crossover properties obtained from this analysis are compared with the existing experimental results.

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Influence of stiffeners on the performance of blind-bolt end-plate connections to CFST columns

  • Ding, Fa-xing;Pan, Zhi-cheng;Liu, Peng;Huang, Shi-jian;Luo, Liang;Zhang, Tao
    • Steel and Composite Structures
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    • 제36권4호
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    • pp.447-462
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    • 2020
  • The paper aims to investigate the mechanical mechanism and seismic effect of stiffeners in blind bolt endplate connection to CFST column. A precise 3D finite element model with considering the cyclic properties of concrete and steel materials was established, and the efficiency was validated through monotonic and cyclic test data. The deforming pattern and the seismic performance of the unstiffened and stiffened blind bolt endplate connections were investigated. Then a parametric analysis was conducted to analyze the contribution of stiffeners and the joint working behaviors with endplate under cyclic load. The joint stiffness classifications were compared and a supplement stiffness classification method was proposed, and the energy dissipation ability of different class connections were compared and discussed. Results indicated that the main deformation pattern of unstiffened blind bolt endplate connections was the local bending of end plate. The vertical stiffeners can effectively alleviate the local bending deformation of end plate. And influence of stiffeners in thin endplate and thick endplate was different. Based on the stiffness of external diaphragm welded connection, a more detailed rigidity classification was proposed which included the pin, semi-rigid, quasi-rigid and rigid connection. Beam was the main energy dissipation source for rigid connection. For the semi-rigid and quasi-rigid connection, the extended endplate, stiffeners and steel beam would all participate in the energy dissipation.

Studies into a high performance composite connection for high-rise buildings

  • Lou, G.B.;Wang, A.J.
    • Steel and Composite Structures
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    • 제19권4호
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    • pp.789-809
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    • 2015
  • This paper presents experimental and numerical studies into the structural behavior of a high performance corbel type composite connection adopted in Raffles City of Hangzhou, China. Physical tests under both monotonic and quasi-static cyclic loads were conducted to investigate the load carrying capacities and deformation characteristics of this new type of composite connection. A variety of structural responses are examined in detail, including load-deformation characteristics, the development of sectional direct and shear strains, and the history of cumulative plastic deformation and energy. A three-dimensional finite element model built up with solid elements was also proposed for the verification against test results. The studies demonstrate the high rigidity, strength and rotation capacities of the corbel type composite connections, and give detailed structural understanding for engineering design and practice. Structural engineers are encouraged to adopt the proposed corbel type composite connections in mega high-rise buildings to achieve an economical and buildable and architectural friendly engineering solution.

차단기와 모선과의 연결시 가터스프링에 의한 접촉력의 측정 및 설계 고찰 (Measurement and Design Review of Contact Force by Garter Spring in Connection between Circuit Breaker and Bus Bar)

  • 조상순;안길영;박우진;오일성
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.942-945
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    • 2002
  • A garter spring, which is a long. special, close-coiled extension spring with its ends joined to form a ring, is used in connection between vacuum circuit breaker and bus bar in switchgear. To carry short-time current and resist welding at the contact surface in the connection, the garter spring must transmits an uniform contact force to the contact surface through the contact chips arranged in the circumference of bus bar. In this paper, the system for measurement of the contact force by the garter spring is developed. Using the developed measurement system, the design of the connection structure including the garter spring is reviewed to obtain the uniform contact forces in all of contact chips.

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Effect of a two bearing lines deck on the bridge substructure

  • Shaker, Fatemeh;Rahai, Alireza
    • Structural Engineering and Mechanics
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    • 제81권2호
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    • pp.117-129
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    • 2022
  • This research evaluated the different types of deck to pier connections effects (one or two elastomeric bearing lines and rigid) on a concrete bridges. Three-dimensional bridge models behavior with different deck to pier connections and different distances of two bearing lines were studied under the service load. Also, the detailed connection system with two elastomeric bearing lines was modeled to evaluate the effect of changing distance between two-lines. Results indicated that the proper location of elastomeric bearings has a major impact on the transferring forces to the substructure. Double elastomeric bearing lines have a behavior between one line and rigid connections. Transferring bending moment to the substructure in two-lines is more than the corresponding value of the one line. Moreover, an increase in the distance of two-lines lead to a significant increase in the rotational stiffness of the connection, and an analytical solution was investigated for their relation. In fact, the semi-rigidity effect of this connection and its change due to the distance of bearings should be considered in the design process.

Numerical assessment of post-tensioned slab-edge column connection systems with and without shear cap

  • Janghorban, Farshad;Hoseini, Abdollah
    • Computers and Concrete
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    • 제22권1호
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    • pp.71-81
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    • 2018
  • Introduction of prestressed concrete slabs based on post-tensioned (PT) method aids in constructing larger spans, more useful floor height, and reduces the total weight of the building. In the present paper, for the first time, simulation of 32 two-way PT slab-edge column connections is performed and verified by some existing experimental results which show good consistency. Finite element method is used to assess the performance of bonded and unbonded slab-column connections and the impact of different parameters on these connections. Parameters such as strand bonding conditions, presence or absence of a shear cap in the area of slab-column connection and the changes of concrete compressive strength are implied in the modeling. The results indicate that the addition of a shear cap increases the flexural capacity, further increases the shear strength and converts the failure mode of connections from shear rigidity to flexural ductility. Besides, the reduction of concrete compressive strength decreases the flexural capacity, further reduces the shear strength of connections and converts the failure mode of connections from flexural ductility to shear rigidity. Comparing the effect of high concrete compressive strengths versus the addition of a shear cap, shows that the latter increases the shear capacity more significantly.

Dynamic behaviour of semi-rigid jointed cold-formed steel hollow frames

  • Joanna, P.S.;Samuel Knight, G.M.;Rajaraman, A.
    • Steel and Composite Structures
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    • 제6권6호
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    • pp.513-529
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    • 2006
  • This paper deals with the dynamic behaviour of cold-formed steel hollow frames with different connection stiffnesses. An analytical model of a semi-rigid frame was developed to study the influence of connection stiffnesses on the fundamental frequency and dynamic response of the frames. The flexibilities of the connections are modeled by rotational springs. Neglect of semi-rigidity leads to an artificial stiffening of frames resulting in shorter fundamental period, which in turn results in a significant error in the evaluation of dynamic loads. In the seismic design of structures, of all the principal modes, the fundamental mode of translational vibration is the most critical. Hence, experiments were conducted to study the influence of the connection stiffnesses on the fundamental mode of translational vibration of the steel hollow frames. From the experimental study it was found that the fundamental frequency of the frames lie in the semi-rigid region. From the theoretical investigation it was found that the flexibly connected frames subjected to lateral loads exhibit larger deflection as compared to rigidly connected frames.

횡하중을 받는 반강접 철골 골조의 유연도에 관한 연구( II ) -골조 해석모형을 중심으로- (A Study on the Flexibility of Semi-Rigid Steel Frames under Lateral Loadings( II ))

  • 강철규;한영철;이갑조
    • 한국강구조학회 논문집
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    • 제8권4호통권29호
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    • pp.121-131
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    • 1996
  • Semi-rigid frames are frames for whcih the connections joining the beam and column are neither fully rigid nor perfectly pinned. In reality, all steel frames are semi-rigid in nature as all connections exhibit a certain degree of flexibility under loads. For semi-rigid frmaed structures, it is tended to reduce more rigidity of the member for the nonlinear behavior of connections and the P-delta effects of framed structure. To predict the actual behavior of semi-rigid steel frames, a more realistic analysis methods which explicitly takes into account the effect of connection flexibility should be used. In this research, the effect of connection flexibility in the semi-rigid structure has been investigated. To predict the response of flexibility connected frames, the algorithm of semi-rigid steel frame is developed using connection model having nonlinear spring on end of beam.

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전체해석과 국부해석 조합법을 이용한 국부결함이 있는 트러스교 응력이력해석 (Stress History Evaluation for Truss Bridge with Local Damages by Using Global-Local Model Combination)

  • 김효진;박상일;배기훈;이상호
    • 한국재난관리표준학회지
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    • 제3권1호
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    • pp.33-42
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    • 2010
  • 본 논문에서는 전체해석과 국부해석 조합방법을 이용하여 국부손상 또는 균열의 영향을 반영한 트러스교의 전체지간에서의 응력거동을 예측하였다. 이를 위해서 전체 구조체는 프레임요소에 의한 해석을 수행하고 국부 상세부분은 쉘요소에 의한 해석을 수행하여 두 결과를 조합함으로써 교량의 연결부처럼 응력분포가 복잡한 부분에서 이동하중에 따른 응력이력을 손쉽게 산정하게 된다. 트러스 연결부의 실제 기하학적 형상 및 강성을 전체 프레임해석에 고려하기 위해 국부 쉘모델과 프레임모델의 변위 비교를 통해 프레임 모델의 단면수정계수를 산정하였으며, 실제 공용중인 트러스교의 실험값과 해석값을 비교하여 전체해석-국부해석 조합방법을 검증하였으며, 더 나아가 국부손상의 영향이 반영된 국부 쉘모델 해석결과를 전체해석에 반영시켰다.

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반강접 접합부를 갖는 평면 강골조의 거동에 관한 해석적 연구 (Analytical Study on Behaviour of Plane Steel Frame with Semi-Rigid Beam-to-Column Connection)

  • 김종성
    • 한국강구조학회 논문집
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    • 제21권5호
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    • pp.483-492
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    • 2009
  • 소성영역에서 부재의 강성감소, 휨효과 및 잔류응력의 영향을 고려하면서 극한 한계상태에서 강골조의 거동을 평가하기 위해 개선 소성 힌지법을 이용하여 평면강골조의 비선형해석을 실시하고, 강접 및 반강접 평면강골조의 다양한 모델에 대한 수치해석을 통하여 거동을 평가하는데 목적이 있다. 그리고 상용프로그램을 이용한 해석결과를 이용하여 반강접율의 변화에 따른 골조의 거동을 분석한다.