Structural steel members are subjected to corrosion due to environmental condition. As a result, there is decreasing in the cross-section properties of the member. This causes different stability problems and reduction in the load carrying capacity of members. Then, the probability of failure, P_f increases due to corrosion. The need arises to determine expected level of safety for such members and systems. Besides, reliability of the steel structure is also effected by the structural stability problems that result decreasing in the resistance. Lateral torsional buckling is one of the most encountered problems in steel members and affected by the critical moment which is a function of lateral and torsional stiffness. Critical moment depends on the material properties, boundary conditions, unbraced length, load pattern, and the member’s cross section. Under the corrosion, it is inevitable to observe changing in some of properties. In this study, a damage model to determine the reliability of a corroded I-shape steel member under linear moment gradient is developed considering corrosion exposure time. Uniform and varying thickness loss models are considered to show the corrosion effect. Influence of environmental condition on the load carrying capacity of the members is considered and their effects on member design is evaluated. As a result, it is concluded that load carrying capacity of steel members degrades and safety of them adversely effected. With presented formulas, it is ensured that the load carrying capacity and reliability indices of the steel members can be calculated practically under the examined situations

结构钢构件由于环境条件而受到腐蚀。结果，构件的横截面特性降低。这会导致不同的稳定性问题和构件承载能力的降低。那么，失败的概率，P _f因腐蚀而增加。需要确定此类成员和系统的预期安全水平。此外，钢结构的可靠性还受到结构稳定性问题的影响，导致阻力下降。横向扭转屈曲是钢构件中最常见的问题之一，受临界力矩的影响，临界力矩是横向和扭转刚度的函数。临界力矩取决于材料属性、边界条件、无支撑长度、载荷模式和构件的横截面。在腐蚀下，不可避免地会观察到一些性能的变化。在这项研究中，考虑腐蚀暴露时间，开发了一种损伤模型，用于确定线性力矩梯度下腐蚀的工字钢构件的可靠性。均匀和变化的厚度损失模型被认为是显示腐蚀效果。考虑了环境条件对构件承载能力的影响，并评估了它们对构件设计的影响。结果，得出结论，钢构件的承载能力下降并且对其安全性产生不利影响。给出的公式保证了钢构件的承载能力和可靠度指标在检验情况下可以实际计算