ロンジ•トランス接合部近傍の応力分布に及ぼす縦通不連続量の影響に関する研究

摘要

In the ship-hull design phase, the distance of longitudinal discontinuity is enlarged, by up to 100 mm for example, until its effect is thought to be minimized. To control tolerance, we used a technique to estimate the coefficient of the misalignment effect: the ratio of the stress with misalignment to the stress without misalignment. Current methods, created using Strength-of-Materials misalignment model, cannot be applied in the design phase. Longitudinal discontinuity models are needed, as there have been no studies of these joints and it is impractical to do finite element (FE) analysis in each case. We propose an estimation method of the coefficient of discontinuity effect in cruciform welded joint with shell plate. First, we created a new equation to estimate the coefficient in Strength-of-Materials model. Second, we found the membrane component of a discontinuous member stress is reduced because of the shell plate and the coefficient converges given a certain discontinuity value. Third, a modified equation taking the effect into account indicates the coefficient in the joint with shell plate.%船体構造設計時に開口や機器配置等を考慮し部材配置を行うと，大骨位置にて防撓材同士の取り合い位置が一致しないことがある.本研究ではその取り合い位置がずれる距離を不連続量と呼ぶことにするが，発生応力への影響を最小限に留めるため不連続量を一定以上に拡げる設計を行うことが一般的である.著者らはこの量を経験的に100mm程度だと考えており，船殻設計者の間でも妥当な値と見なされているようであるが，これまで定性的•定量的に検討された研究成果は公表されていない.