• CN:11-2187/TH
  • ISSN:0577-6686

›› 2011, Vol. 47 ›› Issue (20): 41-44.

• 论文 • 上一篇    下一篇

起重机焊接箱形梁疲劳可靠度及初始裂纹的蒙特卡罗仿真

徐格宁;范小宁;陆凤仪;杨恒   

  1. 太原科技大学机电工程学院
  • 发布日期:2011-10-20

Monte Carlo Simulation of Fatigue Reliabilities and Initial Cracks for Welded Box Girders of Crane

XU Gening;FAN Xiaoning;LU Fengyi;YANG Heng   

  1. Mechanical & Electronic Engineering College, Taiyuan University of Science and Technology
  • Published:2011-10-20

摘要: 断裂力学已被学术界公认是一种估算焊接结构件疲劳寿命最有效的解决方法,但在该方法的应用过程中,还存在着一些混乱现象,尤其对疲劳寿命影响较大的初始裂纹在现有技术难以检测的情况下,不同学者往往给出不同的假设,造成所评估的疲劳寿命相差很大。针对这些状况,分析并澄清在应用断裂力学理论进行焊接结构件疲劳可靠度估算中,应力幅的正确使用及初始裂纹和临界裂纹对疲劳寿命的影响,应用蒙特卡罗法对起重机焊接箱形梁进行疲劳可靠度的仿真估算,并通过试验结果的验证,研究确定起重机焊接箱形梁初始裂纹的均值和标准差,为今后断裂力学理论的寿命估算提供可靠的参考依据。

关键词: 初始裂纹, 蒙特卡罗法, 疲劳可靠度, 起重机焊接箱形梁

Abstract: At present, it has been widely accepted that fracture mechanics is the most effective approach to assessing the fatigue life of welded structures. But in the use of this method, there existed some ambiguous phenomena. Especially the initial cracks, which have significant effect on fatigue life, are set different values by different researchers when no crack could be detected under the present technology condition. That made the assessed fatigue life different widely. Focusing on these problems, when fracture mechanics is utilized to assess the fatigue reliabilities for the welded structures, analyses and clarifies how to use the stress amplitude rightly and how the initial cracks and critical cracks affect the fatigue life. Meanwhile, for the welded box girders of crane, the Monte Carlo simulation of fatigue reliabilities is performed and through the demonstration of test, the mean and standard deviation of initial cracks are researched and confirmed. The research conclusions would provide reliable reference for the assessment of the fatigue life of fracture mechanics in the future.

Key words: Fatigue reliabilities, Initial cracks, Monte Carlo method, Welded box girders of crane

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