腐蚀与冻融作用下混凝土可靠度模型及分析

Analysis on reliability model of concrete under slat corrosion and freezing-thawing act ion

混凝土结构在腐蚀与冻融双因素作用下的寿命预测问题越来越受到人们重视,但是相关研究甚少。通过总结之前研究得出单一因素与双因素冻融循环破坏次数之间存在Nis=aNbiw幂函数关系,并推导得到当b>0时混凝土可靠度模型可以用三参数Weibull概率模型描述,而当b<0时三参数Weibull分布不再适用。结合现有研究推导得到了腐蚀与冻融循环作用下混凝土可靠度模型并对双因素冻融循环下混凝土进行了可靠度分析。该模型有较好的适用性,为之后的双因素冻融混凝土寿命预测提供了参考依据。

The life prediction problem of concrete structure under slat corrosion and freezing-thawing action draws the attention of more and more people, however related researches are rare.By summarizing previous researches, it could be found that the single and two factors freezing-thawing cycle number could be fitted by a power function as Nis=aNiwb, and proved that when b〉0,the reliability model of concrete could be described as 3-parameter Weibull probability models,while when b〈0,it could not be described as 3-parameter Weibull distribute.According to the present research, a reliability model of concrete under salt corrosion and freezing-thawing action was established and the reliability of the concrete under two factors was analyzed.The model had a satisfactory feasibility and provided references for later researches on the life prediction of concrete under two factors freeze-thawing action.