【摘要】 我国现有大量钢筋混凝土T梁结构,随着服役时间不断延长,在大气环境的作用下均存在不同程度的老化和破坏问题。该文根据混凝土碳化及钢筋锈蚀的机理,考虑抗力随时间变化,对一座桥梁进行时变可靠度分析,同时对比分析各种破坏因素对结果的影响,发现在结构抗力衰减的作用下,该桥在服役基准期50 a时已经不能达到可靠度指标为4.2的要求。分析结果表明,钢筋锈蚀对可靠度影响最大,可为桥梁工程耐久性评价提供有意义的参考。更多还原

【Abstract】 There are a great many of the existing steel reinforced concrete T-beam structures.With the continuous lengthening of service life,there are the different levels of aging and demolishing problems under the action of the atmosphere environment.Based on the mechanism of concrete carbonation and steel bar corrosion,the article analyzes the time-dependent reliability of a bridge with the time variation of resistance,and at the same time,compares and analyzes various demolishing factors on the result.It is found that this bridge has been not able to reach the reliability index of 4.2 requirements when its base service period is 50 years under the action of the structural resistance attenuation.The analyzing result makes clear that the corrosion of steel bar has the greatest influence on the reliability able to provide the significant reference for the durability evaluation of bridge engineering.更多还原