北京航空航天大学毕业论文

1000634151118V215.5+5()()20086北京航空航天大学本科生毕业设计（论文）任务书Ⅰ、毕业设计（论文）题目：连续梁振动疲劳的损伤力学分析Ⅱ、毕业设计（论文）使用的原始资料（数据）及设计技术要求： 1. 材料的 S­N 曲线 2. 冲击载荷Ⅲ、毕业设计（论文）工作内容： 1. 查阅文献 2. 连续梁在冲击载荷下的动力响应分析 3. 构建损伤演化方程，用 S­N 曲线拟合材质参数 4. 建立预估梁振动疲劳寿命的损伤力学方法Ⅳ、主要参考资料： 1. 张行，赵军. 金属构件应用疲劳损伤力学. 国防工业出版社. 1998 2. 姚起杭，姚军. 结构振动疲劳问题的特点与分析方法. 机械科学与技术, 2000,19(9):56–58. 3. Ziad A. Hanna. Vibration Fatigue Assessment Finite Element Analysis and Test Correlation. Canada: University of Windsor, 2005. 4. 赵军，张行. 损伤演化模型中的两个问题. 河南大学学报（自然科学版） , 1997,27(3):15–19. 5. 刘思远. 梁的振动疲劳分析. 北京：北京航空航天大学, 2006. 6. 孙伟. 结构振动疲劳寿命估算方法研究. 南京：南京航空航天大学, 2005. 宇航学院（系）飞行器设计与工程（航天工程）专业类 341511 班学生毕业设计（论文）时间： 2008 年 2 月 18 日至 2008 年 6 月 19 日答辩时间： 2008 年 6 月 19 日成绩：指导教师：兼职教师或答疑教师（并指出所负责部分）：系（教研室）主任（签字）：I20086IIANSYSDuhamelANSYSIIIVibrationFatigueDamageMechanicsAnalysisofContinuousBeamsAuthorZouXiTutorMengQingchunAbstractThearticleanalyzedthevibrationfatigueproblemofcontinuousbeamsbasedonContin-uousDamageMechanics(CDM).Thisworkhasintroducedamechanicalmodelofacontinuousbeam,duringthedynamicanalysisofit,theanalyticalsolutionsoftheeigenmodesandfrequenciesofsimplebeamsandcantileversareobtainedbysolvingthevibrationequationincrossdirectionwithStructuralDy-namicsmethodofvibrationmodesuperposition;meanwhile,theFiniteElementMethod(FEM)solutionisalsoobtainedbyusingANSYSsoftwareforcomparison.DynamicresponseofasimplebeamunderharmonicexcitationandimpactloadexcitationisobtainedwithDuhamelintegralmethod.ThenasimpledamageevolutionequationisbuiltbasedonprinciplesofTher-modynamics,andthematerialcoecientsareobtainedbyfittingthefatigueexperimentdatafromamaterialhandbookwithmethodofminimumsquare.Anddamageevolutionacrossthecrosssectionandalongtheaxialdirectionofthebeamisanalyzedbycombiningthedamageevolutionequationwithresultsofdynamicalanalysis,andsoisthetransformationofeigenfre-quenciesofthebeamasitsdamageevolves.ACDMclosedsolutionandaCDMfiniteelementnumericalsolutionwithANSYSsoftwareareintroducedforengineering,andfinallyasamplecomputationisgiven.Keywords:ContinuousBeam,VibrationFatigue,ContinuousDamageMechanics,FatigueLifePredictionIV1121.1































































































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