• Title/Summary/Keyword: membrane structures

Search Result 690, Processing Time 0.025 seconds

A Study on the Stress Concentration at Crack of Membrane Structures (막구조물의 파손단면에서의 응력집중 현상에 관한 연구)

  • Jeon, Jin-Hyung;Jeong, Eul-Seok;Kim, Seung-Deog
    • Proceeding of KASS Symposium
    • /
    • 2005.05a
    • /
    • pp.89-98
    • /
    • 2005
  • Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The material property of the membrane has strong axial stiffness, but little bending stiffness. Therefore membrane structures arc unstable structures initially. These soft structures need to be introduced initial stresses first because of its initial unstable state, and it happens large deformation phenomenon. To find the structural shape after large deformation caused by initial stiffness introduced, we need the shape analysis considering geometric nonlinearity in structural design procedure. In this study, we investigate into the stress concentration at crack of membrane structures. Therefore, using the nonlinear analysis program that NASS (Nonlinear Analysis for Spatial Structures) perform nonlinear analysis, and stress distribution for creak length investigate for using linear elastic fracture mechanics.

  • PDF

A Study on Cutting Pattern Generation of Membrane Structures by Using Geometric Line (막 구조물의 측지선을 이용한 재단도 생성에 관한 연구)

  • Ahn, Sang-Gil;Shon, Su-Deok;Kim, Seung-Deog
    • Proceeding of KASS Symposium
    • /
    • 2005.05a
    • /
    • pp.125-132
    • /
    • 2005
  • Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The material property of the membrane has strong axial stiffness, but little bending stiffness. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation. In shape finding, membrane structures are unstable structures initially. These soft structures need to be introduced initial stresses because of its initial unstable state, and it happens large deformation phenomenon. And also there are highly varied in their size, curvature and material stiffness. So, the approximation inherent in cutting pattern generation methods is quite different. Therefore, in this study, to find the structural shape after large deformation caused by Initial stress, we need the shape analysis considering geometric nonlinear ten And the geodesic line on surface of initial equilibrium shape and the cutting pattern generation using the geodesic line is introduced.

  • PDF

A Study on the Shape Finding and Patterning Procedures for Membrane Structures (막구조의 초기형상 및 재단도 결정알고리즘에 관한 연구)

  • 한상을;이경수;이상주;유용주
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1998.10a
    • /
    • pp.298-305
    • /
    • 1998
  • The purpose of this study is to propose the method of determining the initial fabric membrane structures surface and membrane patterning procedures. Tension structure, such as, fabric membrane structures and cable-net, is stabilized by their initial prestress and boundary condition. The process to find initial structural overall shape of tension structures produced by initial prestress called Shape Finding or Shape Analysis. One of the most important factor for the design of membrane structures is to search initial smooth surface, because unlike steel or concrete building elements which resist loads in bending, all tension structure forces are carried within the surface by membrane stress or cable tension. To obtain initial surface of fabric membrane element in large deformation analysis, the membrane element is idealized as cable using a technique with Force-density method. and that result is compared with well-known nonlinear numerical method, such as Newton-raphson method and Dynamic relaxation method. The shape resulting from Force-density method has been dealt with as the initial membrane shape and used patterning procedures.

  • PDF

Membrane Structures - Their Characteristics and Various Applications -

  • Kawaguchi, Mamoru
    • Journal of Korean Association for Spatial Structures
    • /
    • v.1 no.2 s.2
    • /
    • pp.10-22
    • /
    • 2001
  • A few characteristics of membrane structures which the author thinks important for design are described on the basis of his experience in research and design of this kind of structures. Different in behaviors of air-supported and air-inflated structures are first explained for a better understanding of these structures. Attention is drawn to unfavorable behaviors of an air-beam when it is reinforced by diagonal members. The shallowest membrane structure which can be made as an airdome is pursued, and its application to a metal membrane dome is shown. Attempts which have been made by the author seeking for the possibility of membrane structures made of metal sheet, plastic film with and without reinforcement are described with realized examples. A 100m long jumbo carp is explained as an example of a flying membrane.

  • PDF

Study on Stress Transition Mechanism and Uniaxial Tensile Characteristics by Tensile Fractured Test of Clamping Part of Membrane Structures (막구조 정착부의 인장파단시험을 통한 신장특성 및 응력전달체계에 관한 연구)

  • Kim, Hee-Kyun;Jeon, Sang-Hyeon;Ha, Chang-Woo;Kim, Jae-Yeol
    • Journal of Korean Association for Spatial Structures
    • /
    • v.20 no.3
    • /
    • pp.91-98
    • /
    • 2020
  • For form stability of membrane structures, membrane material is required to be in tension. Therefore, in planning and maintenance management, the engineer should consider enough about introduction of stress during construction and re-introduction of stress after completion. Clamping part is an important portion with the function for introducing tension into membrane materials, and the function to transmit stress to boundary structures, such as steel frames. Then, the purpose of this research is to clarify stress condition and stress transfer mechanism including clamping part of membrane structures, and to grasp the changing tendency of membrane structures with the passage of time. In this research, following previous one, we perform well-balanced evaluation by conducting tensile fractured tests of clamping part's specimens, and by measuring individually the amount of displacement of not only overall specimen's length but membrane material and clamping part. Thereby, we consider the influence the difference in the hardness of edge rope and the difference in the direction of thread affect modification and fracture load.

Comparison of viscous and kinetic dynamic relaxation methods in form-finding of membrane structures

  • Labbafi, S. Fatemeh;Sarafrazi, S. Reza;Kang, Thomas H.K.
    • Advances in Computational Design
    • /
    • v.2 no.1
    • /
    • pp.71-87
    • /
    • 2017
  • This study focuses on the efficiency and applicability of dynamic relaxation methods in form-finding of membrane structures. Membrane structures have large deformations that require complex nonlinear analysis. The first step of analysis of these structures is the form-finding process including a geometrically nonlinear analysis. Several numerical methods for form-finding have been introduced such as the dynamic relaxation, force density method, particle spring systems and the updated reference strategy. In the present study, dynamic relaxation method (DRM) is investigated. The dynamic relaxation method is an iterative process that is used for the static equilibrium analysis of geometrically nonlinear problems. Five different examples are used in this paper. To achieve the grading of the different dynamic relaxation methods in form-finding of membrane structures, a performance index is introduced. The results indicate that viscous damping methods show better performance than kinetic damping in finding the shapes of membrane structures.

Development of a Parametric Design System for Membrane Structures (연성 막구조의 파라메트릭 설계 시스템 개발)

  • Choi, Hyun-chul;Lee, Si Eun;Kim, Chee Kyeong
    • Journal of Korean Association for Spatial Structures
    • /
    • v.16 no.4
    • /
    • pp.29-36
    • /
    • 2016
  • The objective of this research is to development of a parametric design system for membrane structures. The parametric design platform for the spatial structures has been designed and implemented. Rhino3D is used as a 3D graphic kernel and Grasshopper is introduced as a parametric modeling engine. Modeling components such as structural members, loading conditions, and support conditions are developed for structural modeling of the spatial structures. The interface module with commercial structural analysis programs is implemented. An iterative generation algorithm for design alternatives is a part of the design platform. This paper also proposes a design approach for the parametric design of Spoke Wheel membrane structures. A parametric modeling component is designed and implemented. SOFiSTik is examined to interact with the design platform as the structural analysis module. The application of the developed interface is to design optimally Spoke Wheel Shaped Ductile Membrane Structure using parametric design. It is possible to obtain objective shape by controlling the parameter using a parametric modeling designed for shape finding of spoke wheel shaped ductile membrane structure. Recently, looking at the present Construction Trends, It has increased the demand of the large spatial structure. But, It requires a lot of time for Modeling design and the Structural analysis. Finally an optimization process for membrane structures is proposed.

An Estimate for Convergence and Efficiency of Nonlinear Shape Analysis According to the Control Techniques (제어기법에 따른 비선형 형상해석의 수렴성 및 효율성 펑가)

  • Jeong, Eul-Seok;Jeon, Jin-Hyung;Shon, Su-Deog;Kim, Seung-Deog
    • Proceeding of KASS Symposium
    • /
    • 2006.05a
    • /
    • pp.214-223
    • /
    • 2006
  • Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The material property of the membrane has strong axial stiffness, but little bending stiffness. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation. In shape finding, membrane structures are unstable structures initially. These soft structures need to be introduced initial stresses because of its initial unstable state, and happen large deformation phenomenon. Therefore, in this study, to find the structural shape after large deformation caused by initial stress, we need the shape analysis considering geometric nonlinear term. And we investigate the evaluation of shape analysis technique's convergence and efficiency according to the control method

  • PDF

Review of Membrane Tension Maintenance System for Membrane Structures through Membrane Tension Measurement (막장력 측정을 통한 막구조물의 장력 유지관리 시스템 검토)

  • Jin, Sang-Wook;Shon, Su-Deok;Lee, Seung-Jae
    • Journal of Korean Association for Spatial Structures
    • /
    • v.16 no.2
    • /
    • pp.39-45
    • /
    • 2016
  • Membrane structure is a system that is stabilized by maintaining a tensile state of the membrane material that originally cannot resist the bending or pressure. Also, it is a system that allows the whole membrane structure to bear external loads caused by wind or precipitation such as snow, rain and etc. Tension relaxation phenomenon can transpire to the tension that is introduced to the fabric over time, due to the innate characteristics of the membrane material. Thus, it is important to accurately understand the size of the membrane tension after the completion of the structures, for maintenance and management purposes. The authors have proposed the principle of theoretically and indirectly measuring the tension by vibrating the membrane surface with sound waves exposures against the surface, which is compartmentalized by a rectangular boundary, and by measuring the natural frequency of the membrane surface that selectively resonates. The authors of this paper measured the tension of preexisting membrane structure for its maintenance by using the developed portable measurement equipment. Through analyzing the measurement data, the authors review the points that should be improved and the technical method for the new maintenance system of membrane tension.

A Study on The Cutting Pattern Generation of Membrane Structures and Loss Ratio of Febrics According to the Curvature (막구조물의 재단도 작성과 곡률 변화에 따른 손실률에 관한 연구)

  • Jeon, Jin-Hyung;Jeong, Eul-Seok;Shon, Su-Deok;Kim, Seung-Deog
    • Proceeding of KASS Symposium
    • /
    • 2006.05a
    • /
    • pp.205-213
    • /
    • 2006
  • Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation, because the material property has strong axial stiffness, but little bending stiffness. The problem of cutting pattern is highly varied in their size, curvature and material stiffness. So, the approximation inherent in cooing pattern generation methods is quite different. Therefore the ordinary computer software of structural analysis & design is not suitable for membrane structures. In this study, we develop the program for cutting pattern generation using geodesic line, and investigate the result of example's cutting pattern in detail.

  • PDF