• Title/Summary/Keyword: Structural member

Search Result 1,503, Processing Time 0.019 seconds

Structural behavior of aluminum reticulated shell structures considering semi-rigid and skin effect

  • Liu, Hongbo;Chen, Zhihua;Xu, Shuai;Bu, Yidu
    • Structural Engineering and Mechanics
    • /
    • v.54 no.1
    • /
    • pp.121-133
    • /
    • 2015
  • The aluminum dome has been widely used in natatorium, oil storage tank, power plant, coal, as well as other industrial buildings and structures. However, few research has focused on the structural behavior and design method of this dome. At present, most designs of aluminum alloy domes have referred to theories and methods of steel spatial structures. However, aluminum domes and steel domes have many differences, such as elasticity moduli, roof structures, and joint rigidities, which make the design and analysis method of steel spatial structures not fully suitable for aluminum alloy dome structures. In this study, a stability analysis method, which can consider structural imperfection, member initial curvature, semi-rigid joint, and skin effect, was presented and used to study the stability behavior of aluminum dome structures. In addition, some meaningful conclusions were obtained, which could be used in future designs and analyses of aluminum domes.

Reliability analysis of uncertain structures using earthquake response spectra

  • Moustafa, Abbas;Mahadevan, Sankaran
    • Earthquakes and Structures
    • /
    • v.2 no.3
    • /
    • pp.279-295
    • /
    • 2011
  • This paper develops a probabilistic methodology for the seismic reliability analysis of structures with random properties. The earthquake loading is assumed to be described in terms of response spectra. The proposed methodology takes advantage of the response spectra and thus does not require explicit dynamic analysis of the actual structure. Uncertainties in the structural properties (e.g. member cross-sections, modulus of elasticity, member strengths, mass and damping) as well as in the seismic load (due to uncertainty associated with the earthquake load specification) are considered. The structural reliability is estimated by determining the failure probability or the reliability index associated with a performance function that defines safe and unsafe domains. The structural failure is estimated using a performance function that evaluates whether the maximum displacement has been exceeded. Numerical illustrations of reliability analysis of elastic and elastic-plastic single-story frame structures are presented first. The extension of the proposed method to elastic multi-degree-of-freedom uncertain structures is also studied and a solved example is provided.

A Study on the Ultimate Strength Analysis of Frame Structures by Idealized Structural Unit Method (이상화 구조요소법에 의한 골조구조물의 최종강도해석에 관한 연구)

  • 백점기;임화규
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1990.10a
    • /
    • pp.28-33
    • /
    • 1990
  • This paper presents an efficient and accurate method for nonlinear analysis of frame structures by idealized structural unit method. The main idea behind the present method is to minimize the cost of the computational effort by reducing the number of unknowns. An explicit form of the tangential elastic stiffness matrix of the element is derived by using updated Lagrangian approach. An ultimate limit state of the element is judged on the basis of the formation of a plastic hinge mechanism. The elasto-plastic stiffness matrix and the post-ultimate stiffness matrix of the element are formulated by plastic node method. A comparison between the present method is very efficient and accurate because the computing time required is very small while giving the accurate solution.

  • PDF

Strength design criterion for asymmetrically reinforced RC circular cross-sections in bending

  • Hernandez-Montes, E.;Alameda-Hernandez, P.;Gil-Martin, L.M.
    • Computers and Concrete
    • /
    • v.11 no.6
    • /
    • pp.571-585
    • /
    • 2013
  • Asymmetrical reinforcement for circular sections in wall piles is an efficient construction component with reduced embodied energy. It has been proven that asymmetrical reinforced wall piles may save more than 50% of the reinforcement than the traditional symmetrically reinforced circular sections. The use of this new type of structural member increases the number of variables in the design problem, which makes its use by engineers more complicated. In order to facilitate the use of the asymmetrically reinforced piles, this paper presents a criterion for the design of this type of structural member. The chosen criterion has been analyzed with the help of flexural capacity-cost curves. The new criterion is similar to the design procedure traditionally used for RC beams.

Regularizing structural configurations by using meta-heuristic algorithms

  • Massah, Saeed Reza;Ahmadi, Habibullah
    • Geomechanics and Engineering
    • /
    • v.12 no.2
    • /
    • pp.197-210
    • /
    • 2017
  • This paper focuses on the regularization of structural configurations by employing meta-heuristic optimization algorithms such as Particle Swarm Optimization (PSO) and Biogeography-Based Optimization (BBO). The regularization of structural configuration means obtaining a structure whose members have equal or almost equal lengths, or whose member's lengths are based on a specific pattern; which in this case, by changing the length of these elements and reducing the number of different profiles of needed members, the construction of the considered structure can be made easier. In this article, two different objective functions have been used to minimize the difference between member lengths with a specific pattern. It is found that by using a small number of iterations in these optimization methods, a structure made of equal-length members can be obtained.

A Structural Characteristics of Hwatong-Connections in Traditional Mindori Type of Wood Structures (전통 민도리식 목구조 화통맞춤의 구조적 특성)

  • Yu, Hye-Ran;Kwon, Ki-Hyuk
    • Journal of architectural history
    • /
    • v.21 no.3
    • /
    • pp.7-28
    • /
    • 2012
  • This study is intended to Mindori structure which is general private houses' structural type among traditional types and is a basic study to confirm structural characteristics of Hwatong connection which is general connection type of column-beam-cross beam. It is aimed to analyze how main member, column, such as size, figure, thickness of Sungetuk and Dugeup affect on structure. Following conclusions are drawn. 1. According to connection conditions, models with big coefficient of friction show stable hysteretic behavior until the angle rotation of member reaches 1/60 and models with small coefficient of friction show dramatical increase in load after the angle rotation of member reaches 1/24. After the angle rotation of member reaches 1/30, separation distance of members is identified physically and cracks are not observed. 2. Specimens with big coefficient of friction show similar inner force regardless of column size(except column size 150mm) and models with small coefficient of friction show increasing inner force as the column size increases. Specimens with same sectional area have similar inner force even though the column figures are different. The thickness of Sungetuk and Dugeup doesn't affect inner force greatly, however, when the thickness of Sungetuk is thin, it could lead to failure of structure as it breaks. 3. The bigger the size of column and the coefficient of friction are, the smaller Bending stiffness depreciation ratio is. 4. Energy Dissipation Efficiency differs from the coefficient of friction. When the coefficient of friction is big, square column shows bigger than round one and it is bigger when the thickness of Sungetuk and Dugeup is thicker. When the coefficient of friction is small, round column shows bigger than square one.

A Study on Deformation Capacity of High Strength Steel Beam-to-Column Connections According to Welding Detail at Beam End (보 단부 용접상세에 따른 고강도강 기둥-보 접합부의 변형능력에 관한 연구)

  • Oh, Sang Hoon;Park, Hae Yong
    • Journal of Korean Society of Steel Construction
    • /
    • v.26 no.4
    • /
    • pp.335-348
    • /
    • 2014
  • For high-strength steel, it is difficult to be applied to flexible structural member because it have high yield ratio and low basic material's toughness. One of the great problems when using high-strength steel connections is the brittle fracture at the end of the beam member in common with general mild steel connections. In the cases of mild steel connections, it has be developed that special moment frame connection details by reinforcing structural member or improvement of welding access hole. But, it is incomplete at yet about applicability estimation of high-strength steel connections. This study is the initial step research for the applicability estimation of beam-to-column connections being applied to developed high-strength steel, HSA800. And, it studied about structural performance of the high-strength steel connections according to the details of welding access hole through full-scale test and analytical method.

Natural Frequencies of Sinusoidally Nonsymmetrically Tapered Members (정현상으로 Taper진 부재의 고유진동수)

  • 강명진;안성기;이수곤
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2000.04b
    • /
    • pp.263-270
    • /
    • 2000
  • It is generally known that the stress and displacement of a member or a system under dynamic load with frequency ω are magnified by the factor 1/[1-(ω/ω/sub 0/)sup/ 2/]. When the member assumes non-prismatic shape, the natural frequency, ω/sub 0/ is hard or impossible to determine if the conventional method are adopted. In these cases, the numerical methods are provide powerful tools for the solution of frequency problems. In this paper, finite element method is applied to determine the natural frequencies of the non-symmetrically tapered members. The shape of the member is assumed to change sinusoidally along its axis. The results obtained by finite element method are expressed by some simple algebraic equations. The estimated frequencies calculated by the proposed equations coincide well with those by the finite element method.

  • PDF

A Study on Energy Absorption Characteristics of Lightweight Structural Member according to Stacking Conditions (적층구성 변화에 따른 경량화 구조부재의 에너지 흡수 특성)

  • Choi, Ju-Ho;Yang, In-Young
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.21 no.2
    • /
    • pp.241-245
    • /
    • 2012
  • In this study, one type of circular shaped composite tube was used, combined with reinforcing foam and without foam. Furthermore, CFRP (Carbon Fiber Reinforced Plastic) circular member manufactured from CFRP prepreg sheet for lightweight design. CFRP is an anisotropic material which is the most widely adapted lightweight structural member. The crashworthy behavior of circular composite material tubes subjected to static axial compression under same conditions is reported in this paper. The collapse mode during the failure process were observed and analyzed. The behavior of polymeric foams to the tubes crashworthiness were also investigated.

Development of Optimum Design Technique for Bus Window Pillar Member (버스 윈도우 필라 부재의 형상 최적 설계기술 개발)

  • 김명한;김대성;임석현;서명원;배동호
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.7 no.6
    • /
    • pp.156-164
    • /
    • 1999
  • The body structure of a bus is generally assembled by using various spot welded box sectional members. The shape of window pillar joint is ordinarily built up by T-type member. It has been shown that T-type member has problems like high stress concentrations, low fatigue strength and low structural rigidity. In this study, to solve these problems a new approach to optimize the design of the bus window pillar joint was tried by FEM analysis and experiments. To describe the shape of the gusset connecting the vertical and horizontal members of the T-type window pillar joint B-spline curve was adopted and this curve was optimized . It was found that the new model developed could effectively improve fatigue durability an structural rigidity.

  • PDF