• Title/Summary/Keyword: rotational ductility ratio

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A study on rotational behaviour of a new industrialised building system connection

  • Moghadasi, Mostafa;Marsono, Abdul Kadir;Mohammadyan-Yasouj, Seyed Esmaeil
    • Steel and Composite Structures
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    • v.25 no.2
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    • pp.245-255
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    • 2017
  • The performance of an Industrialised Building System (IBS) consists of prefabricated reinforced concrete components, is greatly affected by the behaviour of the connection between beam and columns. The structural characteristics parameters of a beam-to-column connection like rotational stiffness, strength and ductility can be explained by load-rotation relationship of a full scale H-subframe under gravitational load. Furthermore, the connection's degree of rigidity directly influences the behaviour of the whole frame. In this research, rotational behaviour of a patented innovative beam-to-column connection with unique benefits like easy installation, no wet work, no welding work at assembly site, using a hybrid behaviour of steel and concrete, easy replacement ability, and compatibility with architecture was investigated. The proposed IBS beam-to-column connection includes precast concrete components with embedded steel end connectors. Two full-scale H-subframes constructed with a new IBS and conventional cast in-situ reinforced concrete system beam-to-column connections were tested under incremental static loading. In this paper, load-rotation relationship and ratio of the rigidity of IBS beam-to-column connection are studied and compared with conventional monolithic reinforced concrete connection. It is concluded that this new IBS beam-to-column connection benefits from more rotational ductility than the conventional reinforced concrete connection. Furthermore, the semi-rigid IBS connection rigidity ratio is about 44% of a full rigid connection.

An Experimental Study on the Strengh and Ductility of High-Strength Flexural Members (고강도 휨재의 강도와 연성에 관한 실험적 연구)

  • Lee, Seung-Joon
    • Journal of Korean Society of Steel Construction
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    • v.13 no.1
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    • pp.19-28
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    • 2001
  • The strength and ductility of steel flexural members are investigated experimentally in this study. As for the performance evaluation of flexural members. experimental studies on the 9 test specimens were carried out. Four specimens were fabricated from SM490 and five specimens were fabricated from SM570. The experimental results of the specimens were analyzed with focus on the flexural strength and ductility. The experimental results exhibited that all the specimens provided sufficient flexural strengthes which exceeded the nominal flexural strengthes specified in the current Limit State Design Specification by average ratio of 1.22. However. the experimental results showed that the compact-section specimens fabricated from SM570 did not provide the required rotational ductility. The yield-to-tensile strength ratio(YR) of SM570 of about 0.9 might be the causes of such insufficient capacities.

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Inelastic analysis of RC beam-column subassemblages under various loading histories

  • You, Young-Chan;Yi, Waon-Ho;Lee, Li-Hyung
    • Structural Engineering and Mechanics
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    • v.7 no.1
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    • pp.69-80
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    • 1999
  • The purpose of this study is to propose an analytical model for the simulation of the hysteretic behavior of RC (reinforced concrete) beam-column subassemblages under various loading histories. The discrete line element with inelastic rotational springs is adopted to model the different locations of the plastic hinging zone. The hysteresis model can be adopted for a dynamic two-dimensional inelastic analysis of RC frame structures. From the analysis of test results it is found that the stiffness deterioration caused by inelastic loading can be simulated with a function of basic pinching coefficients, ductility ratio and yield strength ratio of members. A new strength degradation coefficient is proposed to simulate the inelastic behavior of members as a function of the transverse steel spacing and section aspect ratio. The energy dissipation capacities calculated using the proposed model show a good agreement with test results within errors of 27%.

Experimental Evaluation for Structural Performance of Hybrid Damper Combining Steel Slit and Rotational Friction Damper (강재 슬릿과 회전 마찰형 감쇠 장치를 결합한 복합 감쇠 장치의 실험적 구조 성능 평가)

  • Kim, Yu-Seong;Kang, Joo-Won;Park, Byung-Tae;Lee, Joon-Ho
    • Journal of Korean Association for Spatial Structures
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    • v.19 no.3
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    • pp.101-109
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    • 2019
  • In order to develop the compatible damping device in various vibration source, a hybrid wall-type damper combining slit and friction damper in parallel was developed. Cyclic loading tests and two-story RC reinforced frame tests were performed for structural performance verification. As a result of the 5-cyclic loading test according to KBC-2016 and low displacement cyclic fatigue test, The hybrid wall type damper increased its strength and the ductility was the same as that of the slit damper. In addition, As a result of the two-layer frame test, the reinforced frame had about twice the strength of the unreinforced frame, and the story drift ratio was satisfied to Life Safety Level.

Performance Evaluation on Blast-resistant of Gastight Door using Numerical Simulation (수치해석을 활용한 가스차단문의 폭발압력저항 성능평가)

  • Shin, Baegeun;Kim, Jiyu;Kim, Euisoo
    • Journal of the Korean Institute of Gas
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    • v.26 no.1
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    • pp.27-33
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    • 2022
  • As the scale of explosions diversifies along with the expansion of gas handling and storage facilities, studies on explosion-proof facilities in preparation for accidents is being actively conducted. The gastight door blocks the expansion pressure caused by blast waves or internal fires, and at the same time protects the personnel and equipment inside. For gastight doors, the regulations related to explosion-proof design are not clearly presented, and studies on the explosion pressure resistance performance evaluation of the facility are insufficient. In this study, the gastight door was modeled in a 3D shape with reference to the regulation ASTM regarding the gastight door standard. Afterwards, evaluation for blast-resistant performance of gastight door using Numerical simulation was evaluated by using ANSYS Explicit Dynamics to compare the deformation.

Suggesting double-web I-shaped columns for omitting continuity plates in a box-shaped column

  • Saffari, Hamed;Hedayat, Amir A.;Goharrizi, Nasrin Soltani
    • Steel and Composite Structures
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    • v.15 no.6
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    • pp.585-603
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    • 2013
  • Generally the required strength and stiffness of an I-shaped beam to the box-shaped column connection is achieved if continuity plates are welded to the column flanges from all sides. However, welding the forth edge of a continuity plate to the column flange may not be easily done and is normally accompanied by remarkable difficulties. This study was aimed to propose an alternative for box columns with continuity plates to diminish such problems. For this purpose a double-web I-shaped column was proposed. In this case the strength and rotational stiffness of the connection was provided by nearing the column webs to each other. Finite element studies on about 120 beam-column connections showed that the optimum proportion of the distance between two column webs and the width of the column flange (parameter ${\beta}$) was a function of the ratio of the beam flange width to the column flange width (parameter ${\alpha}$). Hence, based on the finite element results, an equation was proposed to estimate the optimum value of parameter ${\beta}$ in terms of parameter ${\alpha}$ to achieve the highest connection performance. Results also showed that the strength and ductility of post-Northridge connections of such columns are in average 12.5 % and 54% respectively higher than those of box-shaped columns with ordinary continuity plates. Therefore, a double-web I-shaped column of optimum arrangement might be a proper replacement for a box column with continuity plates when beams are rigidly attached to it.

Analytical Model of Beam-Column Joint for Inelastic Behavior Under Various Loading History (철근콘크리트 보-기둥 접합부 해석모델)

  • 유영찬;서수연;이원호;이리형
    • Magazine of the Korea Concrete Institute
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    • v.6 no.1
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    • pp.120-130
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    • 1994
  • The purpose of this study is to propose the analytical model for the hysteretic behavior of Reinforced Concrete bearn-column joints under various loading history. Discrete line elernents , YVith inelastic rotational spring was adopted to consider the movement of plastic hinging zone influenced by the details of longitudinal reinforcements. Also hysteretic model was constructed by excluding such variables which can not be utilized in dynamic analysis of Reinforced Concrete. structure that it will be adoptable in two-dimensional inelastic frame ardysis with 6-DOF. From the analysis of previous test results, it was found that stiffness deterioration caused by inelastic hysteretic loadings can be predicted by the functron of basic pinching coefficients, ductility ratio.and yield strength ratio of members. Strength degradation coefficients were newly proposed to explain the difference of inelastic behavior of members caused by spacing ratio of transverse steel and sectlon aspect ratio. The energy dissipation capacities calculated using the analytical model proposed in thls paper show a good agreements w~lh test results by an error of 10~20%.

Seismic Performance of Built-up Concrete Filled Square Composite Column-to beam Connection with Through Diaphragm (관통형 다이아프램을 갖는 조립형 콘크리트 충전 각형 합성기둥-보 접합부의 내진성능)

  • Kim, Sun Hee;Yom, Kyong Soo;Choi, Sung Mo
    • Journal of Korean Society of Steel Construction
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    • v.26 no.5
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    • pp.431-439
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    • 2014
  • Concrete filled tubular columns are widely used because the mutual reaction between the concrete and the tube improves strength and ductility of the columns. In an attempt to secure efficient use of members, built-up square columns featuring large width-thickness ratio and the use of thin steel plates are suggested in this study. In order to evaluate the structural characteristics and seismic performance of the column-to-beam connections of the new shape columns, cyclic load test of T-shaped column-to-beam connections was conducted with variables of diaphragms and concrete-filling. Moment-rotational angle relationship, dissipated energy and failure behavior were compared to evaluate stress transfer mechanism of the new shape built-up square column-to-beam connections associated with the variables.