钢轨可靠度分析-道路与铁道工程专业论文.docxVIP

西南交通大学硕士学位论文 III 摘要 ，，结构可靠度设计是目前国内外结构设计的主要发展方向。实现轨道设计 ．n定值设计向可靠度设计的转变，不仅符合结构设计和我国铁路技术发展的 犬方向，同时也是当前铁路运输的迫切需要。钢轨是轨道结构的重要组成部 分，，本文对无缝线路钢轨可靠度进行了探讨，主要研究内容及研究成果如下： ／’——————————————一 首先，简单介绍了可靠度的一些基本理论及几种常用的可靠度计算方法， 其中重点介绍了蒙特卡罗方法在钢轨可靠度计算中的应用。讨论了钢轨的失 效模式和设计基准期，建立了钢轨极限状态方程的功能函数。 其次，对钢轨可靠度分析中涉及的随机变量如轮载力、轨下胶垫刚度、 道床路基联合刚度、温度应力及钢轨疲劳极限强度的概率分布类型和统计特 征进行了详细讨论。 最后，采用有限单元法与蒙特卡罗法相结合的方法对50kg／m轨和60kg／m 轨的可靠度进行了计算，根据“校准法”的思想得到了钢轨目标可靠指标的 建议值，指出了现行钢轨磨耗标准所存在的问题。／在此基础上，对钢轨的磨 耗限进行了初步探讨，认为60kg／m轨的垂直磨耗限可以提高5mm，具有相 当大的经济价值。)—户7、—7 【关键词】 瓣分术巧 I  西南交通大学硕士学位论文 Ⅳ Abstract It’S a major development trend tO design structures with the reliability method in the field of structural design at home and abroad．To change the method of the raih、’ay track structures’design from deterministic method into reliability method not only is the development trend of the railway’S technique， but also is the imperative demand of the present railway trafile．The steel rail is an important components of the railway track structures The thesis has probed into the reliability of the steel rail which is located in the Continuous Welded Railway．The following are the thesis’major research contents and achievements． First，some fundamental theory and several regular calculation methods are introduced．And the paper centers on the introduction of the appliance of the Monte—Carlo method in the calculation of the steel rail’S reliability．The failure mode and the design reference period of the steel rail are discussed，and the steel rail’S performance function at limit state is established too． Second，the random variables in reliability analysis of the steel rail are discussed．These random variables include the wheel load，the stiffness of the rubber pad and the bed，the temperature stress and the fatigue ultimate strength of the steel rail．And their probability distributions and parameters are discussed thoroughly． Last，the reliability of 50kg／m—rail and 60kg／m—rail is calculated by using the method combing the Mote·Carlo imitation w