Summary: | 碩士 === 國立臺灣大學 === 工程科學及海洋工程學研究所 === 102 === Recently Aluminum alloy has been applied for high speed vessel because its density is 1/3 of steel, and has good corrosion resistance. For aluminum structure not only the equivalent yield strength need be considered, the strength reduction due to heat affected after welding, and relative lower fatigue strength should be taken account, if the design of aluminum structure member is based on the exsisted desing of steel structure, the fatigue life and the ultimate strength of structure member should be assessed. In this work the Palmgren-Miner rule was used to predict the fatigue life of aluminum of structure member, the crack length within specified time period by the crack growth speed method was also predicted for member with initial crack. After assessment of fatigue strength, the structural member should be modified if its fatigue life is shorter than required service life. Comparrision study of ultimate strength for deck structure between lightweight extrusion deck panel and traditional deck structure by applied displacement control and bending moment control.
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