在巨觀的船舶結構模型中,雙層底與雙層殼結構,均屬金屬三明治結構。過去由於電銲技術與設備的限制,高度低於人高的金屬三明治很少被採用,近年來由雷射銲接技術的精進與設備經濟化的趨勢,先進雷射銲接鋼三明治結構在歐美造船界再度被重視。三明治結構特性如結構強度的均勻性、同樣彎曲強度的重量輕量化與厚度降低、加工表面的優值化、夾層預留空間的應用等,比傳統的肋骨加強板,深樑結構、以及雙層殼結構更具優勢。本文著重在船舶碰撞問題,對金屬三明治結構的研究重點也在抗撞能力研究,比較不同夾心結構在抗撞能力上的不同。 本文先探討格狀夾心與桁架夾心之三明治結構的抗撞能力,將兩者之抗撞阻力與結構消能特性與單一平板互相比較,並將有限元素法分析結果與McShane(2005)之試驗結果比較其阻抗力與撞擊深度分佈趨勢。接著選擇Paik(1999)系列合金蜂巢狀三明治結構試驗模型之部分有限元素進行撞擊分析,比較分析結果與試驗結果之差異。最後以相同的材料重量為基礎,選擇格狀夾心、桁架夾心、蜂巢狀三明治板與肋骨加強板,進行有限元素分析以比較四者抗撞阻力與消能曲線。
Generally, the double bottom and double hull of ships are two types of metal sandwich structures. In the past decades, because of the limitation of the welding technology and the size of facilities, the metal sandwich structures with depth less than human’s height were difficult to be constructed. Recently, the technology of laser welding are growing up and its investments are strongly reduced, the metal sandwich structure are taken into consideration by the American and European ship yards. The advantageous of sandwich structure such as the uniformity of strength, lighter weight for the same bending strength and the reserved space within double hull , are superior to conventional structures. The paper focus on ship collision problems, and hence the crashworthiness of metal sandwich structure was examined, and different type of core structures are compared. In this paper, impact responses of sandwich structure with square-honeycomb core and truss-core were analyzed first. Both resistant force and energy dissipation for the two sandwich types structures are compared with monolithic plate with the same weight. The results are compared with experimental results by McShane (2005) to varify the tendency of resistant force versus penetrated depth. Subsequently, some experimental models from the series test of aluminum honeycomb sandwich structures by Paik(1999) are selected no case studies and the FE-analysis were perfomed. The analyzed results were compared with the experiment results to confirm their difference. Finally, resistant force and energy dissipation of sandwich structures with different core structures with the same weight are compared.