对于复杂的工程结构,采用通常的可靠性分析方法对其进行可靠性分析往往会受到很多实际困难限制。我们提出的结构可靠性分析的Monte Carlo有限元法综合了有限元法和Monte Carlo法的优点。不仅可用于求解随机变量为任意分布的结构可靠度,而且能用于求解任意复杂结构的可靠度。本文对四川油气田的井口关井压力进行了统计分析,并利用Monte Carlo有限元法对结构复杂的井口套管头进行了可靠性分析,提出了对其进行可靠性设计的改进意见。 For complex engineering structures, reliability analysis using the usual methods of reliability analysis often suffers from many practical difficulties. The proposed Monte Carlo finite element method for structural reliability analysis combines the advantages of finite element method and Monte Carlo method. It can not only be used to solve random distribution of random structural reliability, but also can be used to solve the reliability of any complex structure. In this paper, the pressure of wellbore shut-in in Sichuan oil and gas field is statistically analyzed, and the reliability of wellhead casing head with complex structure is analyzed by Monte Carlo finite element method. Some suggestions are put forward to improve its reliability.