RAPID SCREENING METHOD TO DETERMINE HYDRAULIC ACTIVITY INDEX OF PUMICEOUS POZZOLANIC MATERIALS FROM GUATEMALA, USING XRD ANALYSIS.

摘要

One disadvantage of evaluating the quality of natural pumiceous pozzolans for cement production by traditional screening methods is the time lapse, of at least 28 days needed to calculate it. The main objective of this study was to determine if an XRD analysis could be used to have a faster and precise screening method of different pumiceous pozzolanic materials in the Guatemala region. A quantification of amorphous material (glass content) was measured using a Panalytical Empyrean XRD, using corundum as internal standard. We tested 37 samples from four different sources, 4 samples from the CCRL Pozzolan Program and 5 samples of natural quartz were included. Correlation between estimated amorphous content vs. ASTM C-311hydraulic activity index showed an index of r = 0.83 & r = 0.91 for 7 and 28 days respectively. Those outcomes sustain the idea that XRD methods can be used to rapid screen the quality of pumiceous pozzolans used in cement production process. This study is relevant because it can be a faster way to filter data coming from different pumiceous pozzolan sources, which can improve quality control decisions of the mining engineers and cement production processes and help manage them in an more efficient and effective way.