• Title/Summary/Keyword: Plastic Buckling

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Sensitivity Analysis and Optimal design for the Elasto-plastic buckling of Vehicle Structures (차체구조물의 탄소성좌굴에 관한 민감도해석과 최적설계)

  • Won, Chong-Jin;Lee, Jong-Sun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.7 no.5
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    • pp.106-112
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    • 1998
  • Experience and experiments show that in many cases the buckling limit is reached at a much smaller load level than is predicted by linear buckling analysis. In this paper, it is considered linear and nonlinear of plane vehicle structure and estimates design sensitivity of the cross sectional area that is composed plane vehicle structure and performs optimal design. It compares linear vehicle structure with nonlinear vehicle structure for optima design result that is selected constraint condition of buckling load.

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In-plane buckling strength of fixed parabolic arch (고정지점 포물선 아치의 면내 좌굴강도)

  • Moon, Ji Ho;Yoon, Ki Yong;Cho, Yong Rae;Lee, Hak Eun
    • Journal of Korean Society of Steel Construction
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    • v.18 no.3
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    • pp.301-310
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    • 2006
  • If arches are braced by lateral restraints, the ultimate strength of arches is determined by in-plane buckling and plastic bending collapse. This paper is conducted to investigate the in-plane nonlinear elastic and inelastic buckling behavior and the strength of fixed parabolic arches in uniform compresion, as well as to study arch behaviors against non-uniform in-plane compression and bending. As shown by the results, the limit slenderness ratio is suggested to classify the bucklingmode. Buckling strength of fixed parabolic arches under uniform compresion are evaluated using buckling curve for a straight column. Finally, an interaction e quation for arches under combined axial compresion and bending action is proposed.

A Study of the In-plane Rigidity of a Compressed Ship Plate above Buckling Load (압축하중을 받는 선체판의 좌굴후 면내강성에 관한 연구)

  • 고재용;박성현;박주신
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2002.11a
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    • pp.107-112
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    • 2002
  • Basically, ship structure consists of the plate members, and a strength of overall ship structurnds on the stiffness and strength of ship platings. If buckling which causes to deflect ship plate members occurs, the stiffness of ship plate markedly decreases, and thus buckling has a serious effect on the stiffness or strength of overall ship structure. Buckling is one of the most important design criteria when we scantle structure members. In the present study, a inplane rigidity of a compressed ship plate above buckling load is proposed. The proposed inplane rigidity is available in the elastic or elasto-Plastic ranges in order to can out a more efficient and reliable design.

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Prequalification of a set of buckling restrained braces: Part I - experimental tests

  • Stratan, Aurel;Zub, Ciprian Ionut;Dubina, Dan
    • Steel and Composite Structures
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    • v.34 no.4
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    • pp.547-559
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    • 2020
  • Buckling restrained braces (BRBs) were developed as an enhanced alternative to conventional braces by restraining their global buckling, thus allowing development of a stable quasi-symmetric hysteretic response. A wider adoption of buckling restrained braced frames is precluded due to proprietary character of most BRBs and the code requirement for experimental qualification. To overcome these problems, BRBs with capacities corresponding to typical steel multi-storey buildings in Romania were developed and experimentally tested in view of prequalification. The first part of this paper presents the results of the experimental program which included sub-assemblage tests on ten full-scale BRBs and uniaxial tests on components materials (steel and concrete). Two different solutions of the core were investigated: milled from a plate and fabricated from a square steel profile. The strength of the buckling restraining mechanism was also investigated. The influence of gravity loading on the unsymmetrical deformations in the two plastic segments of the core was assessed, and the response of the bolted connections was evaluated. The cyclic response of BRBs was evaluated with respect to a set of performance parameters, and recommendations for design were given.

Study on Section Properties of Deckplates with Flat-Hat Stiffners (Flat-Hat 스티프너를 가진 데크플레이트의 단면 성능에 관한 연구)

  • Ju, Gi-Su;Park, Sung-Moo
    • Journal of Korean Association for Spatial Structures
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    • v.4 no.1 s.11
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    • pp.77-86
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    • 2004
  • It is the buckling of the compression portions of the deckplate that govern its behaviour under wet concrete construction loading. The size and position of intermediate stiffeners in the compression flanges of thin-plate steel decks exert a strong influence on the dominant buckling mode of the flange. Test sections composed of high-strength steel were brake pressed with a variety of Flat-hat intermediate stiffeners in the compression flange forming a progression from small to large stiffeners. The ABAQUS program to determine the effectiveness of intermediate stiffeners in controlling buckling modes is undertaken. A series of specimens are loaded with simple beam. Various buckling wave forms prior to ultimate failure through a plastic collapse mechanism. The experimentally determined buckling stresses are found to be comparable with studies performed using the ABAQUS program analysis and using each country code.

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Fragility assessment of buckling-restrained braced frames under near-field earthquakes

  • Ghowsi, Ahmad F.;Sahoo, Dipti R.
    • Steel and Composite Structures
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    • v.19 no.1
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    • pp.173-190
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    • 2015
  • This study presents an analytical investigation on the seismic response of a medium-rise buckling-restrained braced frame (BRBF) under the near-fault ground motions. A seven-story BRBF is designed as per the current code provisions for five different combinations of brace configurations and beam-column connections. Two types of brace configurations (i.e., Chevron and Double-X) are considered along with a combination of the moment-resisting and the non-moment-resisting beam-to-column connections for the study frame. Nonlinear dynamic analyses are carried out for all study frames for an ensemble of forty SAC near-fault ground motions. The main parameters evaluated are the interstory and residual drift response, brace displacement ductility, and plastic hinge mechanisms. Fragility curves are developed using log-normal probability density functions for all study frames considering the interstory drift ratio and residual drift ratio as the damage parameters. The average interstory drift response of BRBFs with Double-X brace configurations significantly exceeded the allowable drift limit of 2%. The maximum displacement ductility characteristics of BRBs is efficiently utilized under the seismic loading if these braces are arranged in the Double-X configurations instead of Chevron configurations in BRBFs located in the near-fault regions. However, BRBFs with the Double-X brace configurations exhibit the higher interstory drift and residual drift response under near-fault ground motions due to the formation of plastic hinges in the columns and beams at the intermediate story levels.

Local Buckling Behavior of Tapered Members under Cyclic Loading (반복하중을 받는 변단면부재의 국부좌굴 거동)

  • Lee, E.T.;Kim, Jong Won;Park, Ji Hoon;Shim, Ju Yeon
    • Journal of Korean Society of Steel Construction
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    • v.18 no.3
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    • pp.321-329
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    • 2006
  • The use of tapered structural members was first proposed by Ami rikian for the economical use of materials.Generaly, tapered members are used in single-story structures with one or more bays and in cantilevered sections of ate architectural representation. If only focused on the section performance, however, the width-to-thickness ratio or t apered ratio can exced regulations. Such a case requires a study on the behavior of tapered members. To investigate the plastic and local buckling behavior of web-tapered beams, seven steel beams were the tapered ratio and the width-to-thicknes ratio. The results of maximum strength, strength deterioration, and stiffnes deterioration were compared.

Energy demands in reinforced concrete wall piers coupled by buckling restrained braces subjected to near-fault earthquake

  • Beiraghi, Hamid
    • Steel and Composite Structures
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    • v.27 no.6
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    • pp.703-716
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    • 2018
  • In this study, the different energy demands in reinforced concrete (RC) wall piers, coupled by buckling restrained braces (BRBs), are investigated. As well as this, a single plastic hinge approach (SPH) and an extended plastic hinge (EPH) approach is considered for the wall piers. In the SPH approach, plasticity can extend only in the 0.1H adjacent to the wall base while, in the EPH approach, the plasticity can extend anywhere in the wall. The seismic behavior of 10-, 20- and 30-storey structures, subjected to near-fault (NF) as well as far-fault (FF) earthquakes, is studied with respect to the energy concepts involved in each storey. Different kinds of energy, including inelastic, damping, kinetic, elastic and total input energy demand, are investigated. The energy contribution from the wall piers, as well as the BRBs in each model, are studied. On average, for EPH approach, the inelastic demand portion pertaining to the BRBs for NF and FF records, is more than 60 and 80%, respectively. In the SPH approach, these ratios are 77 and 90% for the NF and FF events, respectively. It appears that utilizing the BRBs as energy dissipation members between two wall piers is an efficient concept.

Ductile capacity study of buckling-restrained braced steel frame with rotational connections

  • Mingming Jia;Jinzhou He;Dagang Lu
    • Steel and Composite Structures
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    • v.46 no.3
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    • pp.417-433
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    • 2023
  • The maximum ductility and cumulative ductility of connection joints of Buckling-Restrained Braced Frames (BRBF) are critical to the structural overall performance, which should be matched with the BRB ductility. The two-story and one-span BRBF with a one-third scale was tested under cyclic quasi-static loading, and the top-flange beam splice (TFBS) rotational connections were proposed and adopted in BRBF. The deformation capacity of TFBS connections was observed during the test, and the relationship between structural global ductility and local connection ductility was studied. The rotational capacity of the beam-column connections and the stability performance of the BRBs are highly relevant to the structural overall performance. The hysteretic curves of BRBF are stable and full under large displacement demand imposed up to 2% story drift, and energy is dissipated as the large plastic deformation developed in the structural components. The BRBs acted as fuses and yielded first, and the cumulative plastic ductility (CPD) of BRBs is 972.6 of the second floor and 439.7 of the first floor, indicating the excellent energy dissipation capacity of BRBs. Structural members with good local ductility ensure the large global ductility of BRBF. The ductile capacity and hysteretic behavior of BRBF with TFBS connections were compared with those of BRBF with Reduced Beam Section (RBS) connections in terms of the experimental results.

Elasto-Plastic Postbuckling Analysis of Space Truss Structures (공간트러스구조의 탄소성 후좌굴 해석)

  • Lee, Sang-Hwan;Kwun, Ik-No;Kim, Eung-Kyo
    • 한국공간정보시스템학회:학술대회논문집
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    • 2004.05a
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    • pp.37-42
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    • 2004
  • The primary objective of this paper is to trace the post-buckling behavior of space trusses in the inelastic range. Modeled member material behavior characteristics of struts in the post-critical elasto-plastic stage are determined and three types of idealized hardening rules are described. To perform this analysis, the present work is used the current stiffness parameter method combined with the cylinderical arc-length method. Numerical examples are presented to illustrate the accuracy and the application of the numerical solutions introduced above.

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