The second part concerns about the fracture analysis of cracked metalic structures . the last part investigates the behavior of impact dents on aircraft windshield glass and their possibility to be analyzed using fracture mechanics . in chapter 1 , a review is made to the resent developments of cumulative damage models and fatigue life prediction methodology of composite laminates 本论文研究飞机结构疲劳和损伤容限分析中的若干问题，按研究的对象(材料、结构)可以大致划分为三个组成部分：复合材料层压结构疲劳分析，第一章第三章；金属结构断裂分析，第四、五章；座舱盖玻璃撞击损伤的断裂分析，第六章。
To provide a practical tool for fatigue assessment , this approach is based on the so - called simplified fatigue analysis with the assumption that the long - term stress histogram of the hull structure follows the weibull probability distribution , the s - n curves used in the assessment and evabatbn are the basic design - n curves for non - nodal johts " issued by den ( department of energy of united kingdom ) , combining with computer technology the assessment procedure is programmed , which will indicate the fatigue damage condition and degree of technical status of tanker hulls 在中国船级社( ccs ) 《船体结构疲劳强度指南》和美国船级社( abs ) simplifiedfatigueanalysis的基础上，根据对油轮结构特点和货载特点的分析，讨论了油轮船体疲劳损伤的影响因素，讨论油轮疲劳强度计算方法和计算程序，引入模糊质量评级的方法，建立油轮疲劳损伤评估模型。结合先进的计算机技术，编制出油轮疲劳分析程序，采用典型实船资料，对其疲劳状态进行评估，结果与实际情况比较吻合，表明该程序具有一定的合理性，可作为油轮船公司评价油轮技术状态时在疲劳损伤方面的参考。
Finite element method ( fem ) was used to simulate thermal and vibration problems in stacked - die csp assembly . finite element models and apdl programes were built in ansys to conduct thermal , thermal - mechanical and vibration analysis . the aim of these researches were trying to find some possible reasons and trends which affect the reliability of stacked csp / bga assembly and give some useful suggestions for the packaging design 本论文正是针对以上情况,以采用引线键合工艺的三维叠层csp / bga封装(裸芯片叠装)为研究对象,在有限元分析软件ansys中建立相关的有限元模型,编制了相应的apdl参数化分析程序,进行了温度场分析、热循环加载下的snpb合金焊点疲劳分析和实装pcb板的振动模态分析。
Studying on the shakedown theories and plastic deformation of contact surface layer the shakedown of contact surface layer is related to the strain - hardening models of materials , such as isotropic hardening , kinematic - hardening , and mixed - hardening . the existing results based on experiments and theory show that the shearing strain behavior of contact surface layer caused by friction can be comparatively described with kinematic - hardening 研究中，围绕强化后接触表面疲劳问题，从强化模型选择、接触表层安定性存在的条件及其失效规律，进行了详细的概念定义、定理证明及推论演算等理论工作，为接触表面层安定性的数值模拟和疲劳分析奠定了理论基础。
