• Title/Summary/Keyword: lateral drift

Search Result 58, Processing Time 0.103 seconds

The Shear Lag Phenomenon in Bundled Tube Structure According to the Arrangement of Structural Members (부재배치에 따른 묶음튜브 구조의 전단지연현상)

  • Kim, Young-Chan;Kim, Hyun
    • Journal of the Korean Society of Safety
    • /
    • v.21 no.3 s.75
    • /
    • pp.81-86
    • /
    • 2006
  • The purpose of this study is to examine the effect of column spacing and beam size on the lateral displacement and shear lag phenomenon in bundled tube system. According to the parametric study in which the spacing of columns, the size of columns and girders in bundled tube were selected as a parameter, it is the most efficient to increase the size of the interior columns with the largest reduction of lateral drift if the steel tonnage of a frame can be increased. It was noticed that the shear lag was affected more by the exterior stiffness factor and ratio than by the interior ones when column spacing was changed, and when the size of column was changed, the reverse phenomenon was happened. And The change of column spacing affected shear lag, lateral drift, and tonnage more than that of column size or girder size.

Discrete Optimal Design of Tall Steel Structures subject to Lateral Drift Constraints (횡변위 구속조건을 받는 고층철골구조물의 이산형 최적설계)

  • 김호수
    • Computational Structural Engineering
    • /
    • v.11 no.4
    • /
    • pp.229-237
    • /
    • 1998
  • 본 연구는 횡변위 구속조건을 받는 고층철골구조물의 이산형 최적설계를 위해 효율적인 쌍대알고리즘을 제시하고자 한다. 양함수형태의 횡변위 구속조건을 설정하기 위해 가상일의 원리가 적용되면 고층철골조의 설계변수의 수를 줄여주기 위해 쌍대알고리즘내에 단면특성관계식이 추가된다. 이 알고리즘의 검증을 위하여 횡하중을 받는 네 가지 형태의 고층철골조 예제가 제시되며, 반복과정에서 수렴된 최종물량을 기존의 최적설계방법과 비교해 봄으로써 제시된 알고리즘의 효율성이 검토된다.

  • PDF

Equivalent Beam Model for Flat-Plate Building (무량판 건물의 등가 보 모델)

  • 박수경;김두영;박성무
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1995.10a
    • /
    • pp.312-316
    • /
    • 1995
  • Flat-plate buildings are commonly modeled as two-dimensional frames to calculate lateral drift, unbalanced moments, and shear at slab-column connections. For gravity loads. the slab-column frames are analyzed using equivalent column approach, while equivalent beam approach is typical for lateral loads. The equivalent beam approach is convenient for computer analysis, but no rational procedure exists for determining the effective width of foor slabs. At present, the determination of the equivalent slab width and its stiffness is a matter of engineering judgement. To account for cracking, overly conservative assumptions are made regarding the stiffness of the slab. A rational approach is therefore needed to realistically estimate the equivalent slab width and its stiffness for unbalanced moment and lateral drift calculations. Based on the test results of 8 interior slab-column connections, an equivalent beam model is proposed in which columns are modeled conventionally as a function of column and slab aspect ratios and the magnitude of the gravity load. the proposed approach is verified with selected experimental results and is founded to be practical and convenient for analyzing flat-plate buildings subjected to gravity and lateral loading.

  • PDF

Stiffness-based Optimal Design of Shear Wall-Frame Structure System using Sensitivity Analysis (민감도 해석을 이용한 전단벽-골조 구조시스템의 강성최적설계)

  • Lee Han-Joo;Kim Ho-Soo
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.19 no.1 s.71
    • /
    • pp.63-71
    • /
    • 2006
  • This study presents the effective stiffness-based optimal technique to control Quantitatively lateral drift for shear wall-frame structure system using sensitivity analysis. To this end, the element stiffness matrices are constituted to solve the compatibility problem of displacement degree of freedom between the frame and shear wall. Also, lateral drift constraint to introduce the approximation concept that can preserve the generality of the mathematical programming and can effectively solve the large scaled problems is established. And, the section property relationships for shear wall and frame members are considered in order to reduce the number of design variables and differentiate easily the stiffness matrices. Specifically, constant-shape assumption which is uniformly varying in size during optimal process is applied in frame structure. The thickness or length of shear wall can be changed depending on user's intent. Two types of 20 story shear wall-frame structure system are presented to illustrate the features of the stiffness-based optimal design technique.

The Effects of Coupling Beam on Lateral Drift of High-rise Buildings (고층건물의 횡변위에 대한 커플링보의 효과)

  • Kim, Jin-Sang
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.12
    • /
    • pp.5931-5937
    • /
    • 2011
  • The effects of coupling beam, which is generally used in high-rise building structure system as shear wall-coupling beam, on the lateral drift of high-rise buildings are studied in this paper. Six different analytical models, which are combination of two inputs, such as concrete strength and wall thickness, are selected and analyzed on lateral drifts with different stiffness of coupling beams. MIDAS GEN was used for analysis. Calculated lateral drifts were compared with allowable limits(H/400~H/500) proposed by standard CEN EC 3/1, in order to analyze the control evaluation of coupling beams. Calculated x-direction displacements were 68~87 percent of allowable limit(H/500). With increase of wall thickness(100mm) and concrete strength(5Mpa), eight to ten percent and four percent of x and y-direction displacement were decreased individually. About three percent of lateral displacement was increased with 20 percent decrease of coupling beam stiffness and additional 20 percent decrease resulted in additional five to eight percent increase.

Lateral Drift Control and Resizing Technique for Tall Buildings using Lateral-Stiffness Influence Matrix (횡강성 영향행렬을 이용한 고층건물의 횡변위 제어 및 단면 재산정 방안)

  • 이한주;김치경;김호수
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.15 no.2
    • /
    • pp.271-279
    • /
    • 2002
  • This study develops the module to find the lateral stiffness influence matrix of each story and performs the displacement sensitivity analysis by virtual load method for the efficiency of optimal design using lateral stiffness influence matrix. Also, resizing technique based on the estimated lateral stiffness increment factors is developed to apply directly the results of optimal design. To this end, resizing technique is divided into the continuous and discrete section design methods. And then the relationships between section properties and section size are established. Specifically, an initial design under strength constraints is first performed, and then the lateral load resistant system is designed to control lateral displacements yet exceeding the drift criteria. Two types of 45-story three dimensional structures we presented to illustrate the features of the lateral drift control and resizing technique for tall buildings proposed in this study.

Structural Behavior Characteristics and Efficiency Evaluation of Outrigger System using Stiffness-Based Optimal Design Technique (강성최적설계법을 이용한 아웃리거 시스템의 거동특성 및 효율성 평가)

  • Kim, Ho-Soo;Lee, Han-Joo
    • Journal of Korean Association for Spatial Structures
    • /
    • v.5 no.3 s.17
    • /
    • pp.123-130
    • /
    • 2005
  • This study presents an effective stiffness-based optimal technique to control quantitatively lateral drift and evaluate the structural behavior characteristics and efficiency for tall outrigger system subject to lateral loads. To this end, displacement sensitivity depending on behavior characteristics of outrigger system is established and approximation concept that preserves the generality of the mathematical programming and can efficiently solve large scale problems is introduced. Specifically, under the 'constant-shape' assumption, resizing technique of member is developed. Four types of 50 story frameworks are presented to illustrate the features of the quantitative lateral drift control technique proposed in this study.

  • PDF

Seismic behavior of steel frames with replaceable reinforced concrete wall panels

  • Wu, Hanheng;Zhou, Tianhua;Liao, Fangfang;Lv, Jing
    • Steel and Composite Structures
    • /
    • v.22 no.5
    • /
    • pp.1055-1071
    • /
    • 2016
  • The paper presents an innovative steel moment frame with the replaceable reinforced concrete wall panel (SRW) structural system, in which the replaceable concrete wall can play a role to increase the overall lateral stiffness of the frame system. Two full scale specimens composed of the steel frames and the replaceable reinforced concrete wall panels were tested under the cyclic horizontal load. The failure mode, load-displacement response, deformability, and the energy dissipation capacity of SRW specimens were investigated. Test results show that the two-stage failure mode is characterized by the sequential failure process of the replaceable RC wall panel and the steel moment frame. It can be found that the replaceable RC wall panels damage at the lateral drift ratio greater than 0.5%. After the replacement of a new RC wall panel, the new specimen maintained the similar capacity of resisting lateral load as the previous one. The decrease of the bearing capacity was presented between the two stages because of the connection failure on the top of the replaceable RC wall panel. With the increase of the lateral drift, the percentage of the lateral force and the overturning moment resisted by the wall panel decreased for the reason of the reduction of its lateral stiffness. After the failure of the wall panel, the steel moment frame shared almost all the lateral force and the overturning moment.

A Study on Stiffness-based Optimal Design of Tall Plane Frameworks using Composite Member (합성부재를 이용한 고층평면골조의 강성최적설계에 관한 연구)

  • Kim, Ho-Soo;Lee, Han-Joo
    • Journal of Korean Association for Spatial Structures
    • /
    • v.4 no.3 s.13
    • /
    • pp.77-84
    • /
    • 2004
  • This study presents an effective stiffness-based optimal technique to control quantitatively lateral drift for tall frameworks using composit member subject to lateral loads. To this end, displacement sensitivity depending on behavior characteristics of tall frameworks is established and approximation concept that preserves the generality of the mathematical programming and can efficiently solve large scale problems is introduced. Specifically, under the 'constant-shape' assumption, resizing techniqe of composite member is developed. Two types of 50 story frameworks are presented to illustrate the features of the quantitative lateral drift control technique proposed in this study.

  • PDF

Drift Design Method of High-rise Buildings Considering Design Variable Linking Strategy and Load Combinations (부재 그룹과 하중 조합을 고려한 고층건물 변위조절 설계법)

  • Seo, Ji-Hyun;Park, Hyo-Seon
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.19 no.4 s.74
    • /
    • pp.357-367
    • /
    • 2006
  • Drift design methods using resizing algorithms have been presented as a practical drift design method since the resizing algorithms proposed easily find drift contribution of each member, called member displacement participation factor, to lateral drift to be designed without calculation of sensitivity coefficient or re-analysis. Weight of material to be redistributed for minimization of the lateral drift is determined according to the member displacement participation factors. However, resizing algorithms based on energy theorem must consider loading conditions because they have different displacement contribution according to different loading conditions. Furthermore, to improve practicality of resizing algorithms, structural member grouping is required in application of resizing algorithms to drift control of high-rise buildings. In this study, three resizing algorithms on considering load condition and structural member grouping are developed and applied to drift design of a 20-story steel-frame shear-wall structure and a 50-story frame shear-wall system with outriggers.