桁板構造の最終強度に関する研究(その3) : 桁の横倒れ不安定現象について
スポンサーリンク
概要
- 論文の詳細を見る
It is considered of a fundamental importance in safe, rational and optimum design of ship structures to grasp the true ultimate strength of each structural component of the primary members. In fact, it has often been experienced in structural model testes on deep girders that the ultimate collapse load of the structures is definitely influenced by either local buckling or by the lateral instability of both compression flange and web. This means that the ultimate collapse load of such deep girder structures would be unsafely lowered by these effects than those expected by the plastic analysis on the structure, unless some suitable considerations are made in determining the scantlings of the web and the flange as well as in the arrangement of the stiffeners, tripping brackets, etc.In this paper, the ultimate strength of deep girders is investigated from view point of the safe design against the lateral instability of these members.First, theoretical analysis is made on a deep girder subjevted to bending moment, M (around the strong-axis of the girder) togehter with the axial thrust, N acting in the plane of the web.Analysis based on the flow theory of plasticity is performed by considering the elasto-plastic behavior of the flange and web including the effect of strain reversal, and the successive step by step method is applied to find out the maximum bending moment, M_<m&x> which the girder can carry at the ultimate state.Computation program is developed for the analysis, and the numerical calculations are made by means of electronic computer, in order to investigate the effect of the axial thrust, the span of the girders, the cross sectional properties (falnge breadth b, web depth d, etc.), rigidity of the web stiffeners and the magnitude of initial deflections on the ultimate strength of deep girders.Experimental tests are also carried out model girders with various length of span, in which tested are eight specimens without stiffeners and twelve specimens with web stiggeners of various breadth subjected to a uniform bending moment. Simultaneous measurements and recordings are made on the lateral deflections of flange and web as well as on the strain distributions in the components so as to determine the equivalent length of the span S.Comparisons are made between the test results and the theoretical predictions on the ultimate strength of the girders, and a fairly close agreement is found with each other.Then a survey is made on the conventional scantlings of center girders, transverses, horizontal girders and lingitudenals of large tankers built in the past years to examine the ultimate strength against lateral instability of these members.An approximate formula, b=A√<Sd> is suggested for the design of the deep girders with the minimum breadth of the flange neccessary for assuring their ultimate strength up to a certain prescribed value of the ultimate strength factor, k=M_<m&x>/M_p (M_p being the fully plastic moment of the girders), where the coefficient A is determined by giving the k-value and a parameter η-r which depends upon the bending rigidity of the stiffeners on the web.
- 社団法人日本船舶海洋工学会の論文
著者
関連論文
- 油漕船の横強度に関する実船計測ならびにその解析
- 超大型油槽船「日石丸」の強度実験
- コンテナ船の横強度実船試験
- セミメンブレンLPG船の就航中計測
- IACS縦強度統一規則とその背景(技術規則解説)
- 海洋汚染防止のための原油洗浄方式に関する調査(技術一般)
- トリピングブラケットの座屈強度と桁に対する支持効果について
- 信頼性解析に基づく船体構造設計について
- 船体構造強度の信頼性解析
- LNG船構造解析プログラム(技術一般)
- 波浪衝撃水圧発生装置の試作開発に関する研究(昭和48年学協会刊行物掲載論文再録集)
- 波浪衝撃水圧発生装置の試作開発に関する研究
- 船体横強度のトータルシステムについて
- 船体縦強度解析に関するトータルシステム : タンカーの縦強度について
- NKにおける船体縦強度解析に関するトータルシステムについて(構造解析の電算化小特集)
- 船体強度に関する計測とモニターシステムの開発
- 船体強度に関する長期実船計測(損傷関係)
- 自動車運搬船の横強度に関する実船計測
- コンテナ船の実船計測
- 船体用鋼板の疲労強度について
- LNG船の構造解析
- 自動車運搬船の横強度に関する実船計測
- 船体構造の座屈強度解析について
- コンテナ船縦強度の実船計測および長期予測
- 彎曲部における桁の面材の有効幅
- コンテナ船の横強度解析及び実船計測
- 超大型油送船日石丸の実船計測
- 板構造の座屈に関するシンポジウムの概要紹介
- 桁板構造の最終強度に関する研究(その3) : 桁の横倒れ不安定現象について
- 桁板構造の最終強度に関する研究(その2)
- 二重底構造の強度に関する実船試験
- 二重底構造の強度に関する実船試験
- 桁板構造の最終強度に関する研究(その1)
- 軸力と曲げをうける混用梁の塑性強度について
- 上部構造の有効性について