舰船长期服役,甲板结构易产生初始挠度变形,这会对甲板承载能力带来不利影响。加筋板作为船体甲板结构的主要构成单元,研究初始挠度变形对其极限承载力的影响具有重要意义。为了确定初始挠度变形对加筋板极限承载力的影响作用,根据实际情况假设初始挠度为双三角级数形式,利用Ansys计算分析了整体初始挠度的幅值与半波数对极限载荷的影响和典型位置的应力特性,并得到初始挠度对加筋板极限载荷的影响因子计算方法。计算结果分析表明,随着初始挠度的幅值和半波数的增加,加筋板极限承载力逐渐减小;对于含有某种初始挠度的加筋板,其影响因子主要受加筋板的长宽比、厚度和加强筋间距等因素的影响。
The initial deflection existed on the deck of the surface warship at long service and it brought bad effects on the bearing capacity. Study on the effect of initial deflection on the stiffened plate was meaningful since it was the main unit of the deck. For the research, the mode of the initial deflection was regarded as the double trigonometric series based on the practical truth and the effect of the amplitude and the number of half-waves on the critical stress entirely was analyzed by computing with Ansys. The stress state of the typical location was also discussed. The impact factor of the initial deflection was obtained. Results indicate that with the increasing of amplitude and the number of half-waves, the critical stress decreases. For the stiffened plate with one kind of initial deflection, the impact factor is up to the length-width ratio, the thickness of the stiffened plate and the space between stiffeners.
2017,39(5): 10-15,21 收稿日期:2016-07-11
DOI:10.3404/j.issn.1672-7619.2017.05.003
分类号:U663.6
基金项目:国家自然科学基金资助项目(51309231)
作者简介:刘春正(1991-),男,硕士研究生,研究方向为船舶结构强度与振动
参考文献:
[1] 张涛, 刘土光, 赵耀, 等. 初始缺陷加筋板的屈曲与后屈曲分析[J]. 船舶力学, 2003, 7(1):79-83. ZHANG Tao, LIU Tu-guang, ZHAO Yao, et al. Buckling and postbuckling of imperfect stiffened plates[J]. Journal of Ship Mechaniacs, 2003, 7(1):79-83.
[2] 谭开忍, 李小平. 船体结构极限强度研究进展[J]. 船舶, 2006(5):19-25. TAN Kai-ren, LI Xiao-ping. Research development of ultimate strength of hull structure[J]. Ship & Boat, 2006(5):19-25.
[3] UEDA Y, RASHED S M H, PAIK J K. Effective width of rectangular plates subjected to combined loads[J]. Journal of the Society of Naval Architects of Japan, 1986, 159:269-281.
[4] Nonlinear finite element method models for ultimate strength analysis of steel stiffened-plate structures under combined biaxial compression and lateral pressure actions -Part I:Plate elements.
[5] 万育龙, 朱旭光. 加筋板屈曲和极限强度有限元计算方法研究[J]. 船海工程, 2013, 42(6):17-21. WAN Yu-long, ZHU Xu-guang. Studies on the nonlinear finite element for buckling and ultimate strength of stiffened panels[J]. Ship & Ocean Engineering, 2013, 42(6):17-21.
[6] 罗刚, 吴国民, 汤刚, 等. 侧压对加筋板极限强度的影响分析[J]. 武汉理工大学学报(交通科学与工程版), 2014, 38(6):1400-1403. LUO Gang, WU Guo-min, TANG Gang, et al. Analyse the influence of lateral pressure on the ultimate strength of the stiffen plate[J]. Journal of Wuhan University of Technology(Transportation Science & Engineering), 2014, 38(6):1400-1403.
[7] 单成巍. 循环载荷作用下船体结构的极限强度非线性有限元分析[D]. 武汉:武汉理工大学, 2013. SHAN Cheng-wei. Nonlinear finite element analysis for the ultimate strength of ship structures under cyclic loading[D]. Wuhan:Wuhan University of Technology, 2013.
[8] 杨淼. 基于HCSR的加筋板格非线性屈曲研究[D]. 大连:大连理工大学, 2011. YANG Miao. Analysis of non-linear buckling strength of stiffened plate based on harmonized common structural rules[D]. Dalian:Dalian University of Technology, 2011.
[9] TEIXEIRA A P, IVANOV L D, SOARES C G. Assessment of characteristic values of the ultimate strength of corroded steel plates with initial imperfections[J]. Engineering Structures, 2013, 56:517-527.
[10] DONNELL L H. Effect of imperfection on buckling of thin cylinders under external pressure[J]. Journal of Applied Mechanics. Trans. ASME, 1956, 78.
[11] 张二. 初始几何缺陷对锥-环-柱结合壳力学性能影响研究[D]. 武汉:海军工程大学, 2015. ZHANG Er. Research on the impact of initial imperfection to cone-toroid-cylinder combined shell's mechanical property[D]. Wuhan:Naval University of Engineering, 2015.
[12] 张晓丹, 杨平. 加筋板在轴向压力下的极限强度研究[J]. 武汉理工大学学报, 2011, 35(2):305-308. ZHANG Xiao-dan, YANG Ping. Ultimate strength of stiffened plate under axial compression[J]. Journal of Wuhan Uni versity of Technology, 2011, 35(2):305-308.