Fuzzy Cluster of Corrosion Factors of Soil Environment for Petroleum Asphalt Coated Pipe

By considering the data correlation and using the fuzzy cluster of pattern recognition,the relationship among varions corrosive factors of soil was investigated. Both the matrix of correlation coefficients and the pedigree of factor clusters show that some factors are correlated closely to each other, while others are relatively independent. The correlation coefficients are very high between the parameters such as organic substances and total nitrides, organic substances and microorganism total salts and conductivity, density and void volume etc. However, the CO₃^2-, sulfur oxide bacterias etc., indicate much lower correlation coefficients with soil pH. And the 23 soil corrosive factors are clusterd into 6 distinct clusters under the correlation coefficien value above 0.8. The results of will be helpful to the further study on the soil corrosivity of petroleum asphalt coated pipe.