• Title/Summary/Keyword: Brazier Effect

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A Study on the Brazier Effect of Laminated Plate Structures Having Different Material Constants for Each Element (재료상수가 상이한 요소로 이루어진 적층평판형구조물의 Brazier효과에 관한 연구)

  • 김재열;한상을;권택진
    • Computational Structural Engineering
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    • v.9 no.3
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    • pp.199-207
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    • 1996
  • When an initially straight thin cylinder is bent, there is a tendency for the cross section to flatten. This phenomenon was investigated by L.G. Brazier in 1927 and is called "Brazier Effect" or "Brazier Theory". The main characteristic is the reduction of carrying capacity due to the decrease of bending stiffness by shortening of thickness with the increase of external load. And the relationship of curvature-bending moment becomes a soft spring type as shown in Fig.2. In this paper, the Brazier theory on plate type structures is investigated from the following view points : (1) What is the Brazier effect? (2) the reason of the occurrence of the Brazier effect in plate type structures by using beam model and (3) factors which cause the brazier effect.

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Brazier effect of single- and double-walled elastic tubes under pure bending

  • Sato, Motohiro;Ishiwata, Yuta
    • Structural Engineering and Mechanics
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    • v.53 no.1
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    • pp.17-26
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    • 2015
  • The cross sections of hollow cylindrical tubes ovalise under a pure bending condition, and this reduces their flexural stiffness as their curvatures increase. It is important to accurately evaluate this phenomenon, known as the 'Brazier effect', to understand the bending behaviour of the systems considered. However, if the tubes are supported by an elastic medium or foundation, the ovalisation displacements of their cross sections may decrease. From this point of view, the purpose of this research is to analytically investigate the bending characteristics of single- and double-walled elastic tubes contacted by an elastic material by considering the Brazier effect. The Brazier moment, which is the maximum moment-carrying capacity of the ovalised cross section, can be calculated by introducing the strain energy per unit length of the tube in terms of the degree of ovalisation for the tube and the curvature. The total strain energy of the double-walled system is the sum of the strain energies of the outer and inner tubes and that of the compliant core. Results are comparatively presented to show the variation in the degree of ovalisation and the Brazier moment for single- and double-walled tubes.

An Analysis on Brazier Effect of Cylindrical Tubes Under Pure Bending by Upper Bound Method (상계 해법을 이용한 순수 굽힘하의 원형 튜브의 단면 면화 해석)

  • Koo, Sang-Wan;Kim, Nak-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.4
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    • pp.524-530
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    • 2003
  • This paper presents a new model on deformation characteristics of cylindrical tubes under pure bending. The model is based on the upper bound method that minimizes total strain energy of a system. It does not assume inextensibility condition. Geometric relations and displacement fields are derived by analysis of deformation behaviors of elastic tubes. Simulations are calculated using numerical optimization and integration techniques. The results give information about cross-sectional deformation of cylindrical tubes. Simulation results are compared with available data in literatures, which show that this method predicts deformation characteristics of tube bending process.

The Prediction of Failure Load for an Unsymmetrically Stiffened Circular Composite Spar (비대칭으로 보강된 복합재 원형 스파의 파손하중 예측)

  • Kim, Sung Joon;Lee, Donggeon;Park, Sang Wook
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.7
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    • pp.505-511
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    • 2020
  • The circular composite tubes have been used as a main spar of HALE-UAV(High Altitude Long Endurance-Unmanned Air Vehicle). In this paper, an analytical model is presented for the prediction of the failure load of unsymmetrically stiffened circular spar using a modified Brazier approach. This model was used to predict the moment carrying capacity of the unsymmetrically stiffened circular spar. From the results, we can know that a stiffened cap placed in the top sector of a spar increased the bending capabilities. Four point bending tests were conducted to estimate the effect of the cap on the failure load and compared with the proposed model. And numerical simulations were performed to analyze the behavior of stiffened circular spar. Comparisons of the results from the proposed model with those from experiments and numerical modes show good correlation.

The Effects of Glass Color Tone by Oxidation Power Index (발화력지수(醱化力指數)가 유리색조(色調)에 미치는 영향(影響))

  • Park, Eun-Seong;Park, Byeong-Gi
    • Journal of Korean Society for Quality Management
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    • v.16 no.1
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    • pp.1-7
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    • 1988
  • The most important element upon the quality of family glass products is the color of glass, which is the first object of consumers concern in purchasing. Therefore, colorless and transparent color tone can level up the additional value of the products. But we have produced the glass products in a large quantity by using the automatic tank brazier, chronic problem has been left over the color tone. By compounding and analizing the management techniques applied by peculiar technique and design of experiments pertinently, and by adjusting the decoloring composition ratio, we can contribute to improvement of color tone as well as to the cost reduction by diminishing the unnecessary decoloring agent. Intangible effect was the securing the superiority of quality home and abroad with the improvement of color tone and was taking a triangular position the factors influencing the glass decoloring which had been an unexhausted field. Tangible effect was the reduction of decoloring cost by diminishing the unnecessary oxidant. We registered the optimal composition ratio condition which was searched by applicating the design of experiments. To maintain good color tone, we manage the degree of purity, the most important thing among the items of color tone, continuously by control chart and it has maintained steady state now.

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