Practical Applications of FTIR to Characterize Paving Materials

摘要

Practical applications of Fourier Transform Infrared Spectroscopy in determination of quality and uniformity of antistripping additives, curing membrane compounds, concrete spall repair epoxy materials, evaporation retardants, and concrete cement were investigated. Polymer content in a number of polymer modified asphalt samples were measured based on calibration curves developed for two sets of samples (received from asphalt suppliers to TxDOT) with known polymer contents. Quantification of polymer in asphalt was based on the relationship between the intensity ratio of 966 cm(sup -1)/1375 cm(sup -1) absorption bands to the polymer concentration (wt%). Correlation factor for this relationship for the two sets of data was above 0.96. FTIR technique appears to be capable of quantifying alkali content in concrete cement. A linear relationship was observed relating absorption bands ratio of 750 cm(sup -1)/923 cm(sup -1) to Na(sub 2)O equivalent (as measured with X-ray Fluorescence) with R(sup 2) =0.97. FTIR fingerprints of spall repair patching epoxy, concrete curing membrane, and evaporation retardants were obtained. A separate practical protocol for each kind of analysis was developed for identification and quantification (where applicable) for paving materials constituents.