This research focuses on developing improved methodologies for characterizing and understanding the deterioration and durability of concrete materials, which are primarily governed by the microstructure and the complex interactions between the material's microstructure and environment.  Damage to concrete structures in residential and commercial construction in some areas of the US have been attributed to the iron sulfide mineral pyrrhotite, in which its relative instability results in decomposition with associated staining, expansion, and pop-outs near concrete surfaces or, in severe cases, cracking of the structure.  Other reactive minerals found in aggregate and concrete have also caused similar types of damage to concrete structures.  Specific areas of research include 1) developing test methods to assess the occurence and abundance of reactive minerals, like pyrrhotite, found in aggregate and concrete; 2) identifying reactive mineral/aggregate/concrete reactions and rates so that the most deleterious reactions can be efficiently reduced or eliminated; 3) developing verifiable mathematical and analytical models to quantify the degradation of concrete infrastructure materials; and 4) developing metrologies for potential mitigation strategies, on both materials and structural levels, to manage the deleterious effect of the presence of reactive minerals as a component of aggregate in concrete.