| Through the laboratory simulation experimental,8different types of inorganic andorganic compounds contaminated soil for the distribution of the variability resistivity werestudied under4different pollution content conditions. Meanwhile, with laboratory buried andtested of Q235steel specimen, the distribution rule of corrosion parameters, includingcorrosion morphology, corrosion weight-loss, corrosion dynamic equation parameters,corrosion rate and the effect factor of corrosion rate et.al were researched with5differentcorrosion time. Finally, according to comparison analysis with the result of pH value,resistivity testing and corrosion weight-loss, the reliability of corrosive degree for Q235steelutilized the soil resistivity was analyzed comprehensively.(1) The variation distribution of the average resistivity for different types contaminatedsoil was tested, with9different frequency range of50to1000000Hz, and it can be concludedthat the relationship between average resistivity of different types contaminated soil and thefrequency is a logarithmic function, which the trend reduced with the frequency increasingand the correlation coefficient is in the range of0.73~0.99. Thus the correlation ofcontaminated resistivity and frequency is remarkable.(2) The resistivity distribution of contaminated soil with the constant frequency of50Hzwas analyzed, and it can be found that the resistivity of sulfate and gasoline contaminatedsoils increased with the increasing of contaminated medium content, while the resistivity ofcontaminated soil with other pollution medium decreased with increasing the pollutionmedium content. And the relationship between the contaminated soil resistivity and pollutionmedium content is remarkable, relatively. Additionally, the interrelated relation of thecontaminated soil resistivity and the saturation was also obtained.(3) Sorting the list by ascending counts of the average resistivity for33types soil contaminated by8species medium, under the frequency equal to50Hz condition, it can beconcluded that the resistivity of gasoline contaminated soil (P2, P3and P4) and sulfatecontaminated soil (P4) are larger than the uncontaminated soil (W) resistivity. The resistivityof other contaminated soils is smaller than the uncontaminated soil (W) resistivity, of whichthe resistivity values of sodium chloride contaminated soil (NC4), magnesium chloridecontaminated soil (MC4), sodium sulfate contaminated soil (NS4) and sodium hydroxidecontaminated soil (NO4) are the smallest.(4) With the different types of contaminated soil and different corrosion time, thecorrosion macro morphology of Q235steel was obtained and calculated the corrosionweight-loss, corrosion dynamic equation, corrosion rate and the effect factor of corrosion rate,additionally. According to the results of the corrosion weight-loss, the sort distribution ofaverage corrosion weight-loss ratio and corrosion rate of Q235steel can be attained.Furthermore, with different corrosion time, the regularly ordered for the average value ofeffect factor of contaminated soil corrosion rate was obtained and the three type’s pollutionmedium of contaminated soil that is magnesium sulfate (MS), magnesium chloride (MC) andsulfuric acid (HS) were in the bottom of three types, which the value is equal to1.95,2.20and2.42, respectively. However, the three types pollution medium of contaminated soil that issodium hydroxide (OH), sodium sulfate (NS) and detergent (TD) were in the top of threetypes, which the value is equal to3.59,6.43and7.82, respectively.(5) Combining with the average values sort of resistivity, pH value,224days’ corrosionrate and corrosion rate with different time, the corrosive degree of contaminated soil wasobtained using the method of comprehensive assessment. Then, the Q235steel corrodedburied in sulfate contaminated soil (HS), sodium hydroxide contaminated soil (NO) andgasoline contaminated soil (P) is mainly controlled by the pH value or organic matter, to someextent, the corrosive degree judged by resistivity will be reduced and even misjudgment.Nevertheless, the corrosive degree of Q235steel buried in magnesium chloride contaminatedsoil (MC) and sodium chloride contaminated soil (NC) judged by resistivity will be high orsevere judge. And the corrosive degree of Q235steel buried in sodium sulfate contaminatedsoil (NS) and detergent contaminated soil (TD) judged by resistivity will be low or light judge,while the corrosive degree of Q235steel buried in magnesium sulfate contaminated soil (MS) judged by resistivity will be accurate relatively.This study can provide important basic data and scientific basis, in many respects,including the formulated or revised of national or industry standards, the related design ofconstruction projects selection and protection technology of contaminated soils as well ashave a significant economic and social benefit. |
