aggregate

Research paper: sulfide-bearing aggregate in concrete

Sulfide-bearing Aggregate

Andreia Rodrigues and others at the Centre de Recherche sur les Infrastructures en Beton (Universite Laval) in Quebec, Canada have published a paper on the development of a laboratory test that attempts to reproduce the deterioration of mortar due to the oxidation of sulfide minerals in sulfide-bearing aggregate.

The paper, titled “A new accelerated mortar bar test to assess the potential deleterious effect of sulfide-bearing aggregate in concrete” adds to previous research by the authors on problems related to iron sulfides in concrete in Canada. The full abstract from Cement and Concrete Research is shown below.… Read the rest

Research paper: pyrrhotite in concrete aggregate

Pyrrhotite in Concrete Aggregate

Izelman Oliveira and others at the University Politecnica de Cataluna, Barcelona have published a paper on the oxidation of pyrrhotite in concrete aggregate in Spain. The authors report that the nature of pyrrhotite (in bands) creates planes of weakness that act as preferential paths for oxygen ingress.

The paper, titled “Evolution of pyrrhotite oxidation in aggregates for concrete” follows prior research by Oliveira et al., (2012): Olveira, I., Cavalara, S.H.P., and Aguado, A. (2012). New Unreacted-Core Model to Predict Pyrrhotite Oxidation in Concrete Dams. Journal of Materials in Civil Engineering. 25 (3), 372-381.… Read the rest