Grey Evaluating Of Reinforced Concrete Members Durability Exposed To Common Atmosphere Environment

The paper mainly researched RC Members carbonation. Taking the tested datum to evaluate RC Members durability through the method of gray relation analysis. According to the viewpoint of System science. The factors about effecting RC Members carbonation were divided into two sorts: outer factors and inner ones. The outer factors include medium temperature, relative humility and carbon dioxide concentration. The inner ones are concrete W/C, cement weight in every cube of concrete, RC. Penetration, strength, fly-ash weight etc. for it is so less about multi-factors coupling, the paper takes gray theory to dig some coupling information from the tested datum. On the base of the studied fruit about single factor effecting carbonation. The new ideal for research RC durability comes from it.Firstly, reinforced concrete durability factors serials were confirmed through compositively analyzing outer and inner factors about effecting carbonation. And the gray relative grade between the tested datum serials and the factors optimization serials was calculated to qualitatively analyze reinforced concrete durability according to durability rank-table.Then, analyzing the main carbonation factors to get the gray relative grade between factors and carbonation and carbonation developing essence. From abundant detecting datum, for supplying qualitative gist of quantificational predicting carbonation development.Lastly, GM (1,1) model was taken to predict the carbonation life of reinforced concrete members and GM(1,N) model for analyzing holistically and dynamically reinforced concrete members in common atmosphere environment. In addition, system developing coefficient -a and driving carbonation coefficient b_i with different carbonation factors combination getting from GM (1,N) model were researched. Some information about -a and b, show coupling and carbonation developing after coupling.Through analyzing in theory and material example, GM (1,1) model is feasible and effective for predicting the reinforced concrete members' carbonation life incommon atmosphere environment. And some conclusions about reinforced concrete members durability from GM (1,N) model is accordant with ones of the literature [1] and [6]. On the side, the movement of -a and bi show the coupling between carbonation factors. As to the same factor, the different combination and the different effecting carbonation developing. If one factor is the main one in one kind of factors combination, maybe the factor is not in other sorts of combination. But any kind of factors combination, the driving carbonation coefficient may show the importance sequence about effecting carbonation and show if accelerating or weaken carbonation developing. It regards that accelerating or weakening carbonation developing happened after factors coupling.According to research and discussion in the paper, a new way is provided for research on durability of reinforced concrete. Compared with the method according to reliability used in the field, it is good method for saving material resources, manpower and money, because the method used in the paper is obvious advantage to deal with "small sample" and "less information".