CONCRETE

[:ru]Чекнаворян А. А.[:en]Jeknavorian, A. A.[:] [:ru]канд. техн. наук, ст. научный сотрудник, компания W.R. Grace & Co, Кембридж, штат Массачусетс, США[:en]PhD, Research Fellow, W.R. Grace & Co, Cambridge, MA, USA[:]

Alitinform №3 (30) 2013 г. 88-95 p.

Abstract

The application of pyrolysis gas chromatographic-mass spectrometry (GCMS) has been demonstrated for the determination of chemical additives that are either interground with cement clinker during the manufacture of Portland cement or admixed with a mixture of cement, sand, and stone, and water for the production of concrete. This technique has been found to be readily applicable for selected glycols, alkanolamines, and phenol-based cement grinding aids and naphthalene sulfonate formaldehyde condensate (NSFC) based concrete admixtures. Pyrolysis GCMS methodology can be enhanced through the process of in-situ derivation, which can significantly increase the volatility of additives which would otherwise not thermally desorbs from either cement or concrete. Overall, pyrolysis GCMS analysis of cement and concrete has the potential to be far more specific and less tedious than the common extraction-spectroscopic-based methods currently used.

Key words:

pyrolysis gas chromatographic-mass spectrometry; air entraining agents; naphthalene sulfonate condensate; admixture recovery rate