基于可靠度的输电塔维修决策研究

Decision on Reliability-Based Transmission Tower Maintenance

提出了确定重要构件的两步法,即利用大型有限元软件ANSYS建立输电杆塔结构有限元模型,先对其进行等效风荷载作用下的应力分析以确定必须监测构件以及建议监测构件,再通过构件变化对杆塔一阶振型的灵敏度分析确定构件的相对重要性,从而实现了在实际工程中可根据经济条件和实际需要合理地确定重要构件的目的;基于材料的P-S-N曲线推导了构件的疲劳失效函数和疲劳可靠度函数,对重要构件建立了预防性不完全维修决策模型,在保证构件疲劳可靠度的基础上以单位时间维修成本最小为目标优化维修模型,通过算例分析验证了模型的有效性。

This paper proposes a two-step method to determine the important components,that is,using large finite element software ANSYS to establish the finite element model of transmission tower structure.The paper first makes an analysis on stress under equivalent wind load to determine the components that must be monitored and is advised to be monitored,and then determines the relative importance of the components by the sensitivity analysis of the component changes to the first-order vibration mode of the tower so that the important components can be reasonably chosen according to the economic conditions and practical needs in the actual engineering.In addition,based on the P-S-N curve of the material,the paper derives the fatigue failure function and fatigue reliability function of the component,with the decision-making model of preventive incomplete maintenance of important components established,and optimizes the maintenance model with the aim of minimizing the maintenance cost per unit time under the premise of ensuring the fatigue reliability of components.Finally,the validity of the model is verified by a numerical example.