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Case Study #1: Pointe Du Bois Petrographic Analysis
Extensive cracking and deterioration was occurring in this 100-year-old hydroelectric station. In order to provide an opinion on the cause(s) of the deterioration, a limited petrographic study using select cores from the structure was completed. Scanning electron microscopy combined with energy-dispersive x-ray analysis confirmed significant formations of ettringite within the matrix and verified the presence of alkali aggregate gel.

Case Study #2: Winnipeg International Airport Terminal Building
In order to provide an opinion on the long-term structural integrity of the terminal building, a detailed structural analysis was conducted. Part of this audit included a review of select piles to ascertain the absence or presence of sulphate attack (the conversion of the concrete matrix to gypsum and ettringite). Scanning electron microscopy, combined with energy-dispersive x-ray analysis confirmed the minor presence of sulphate attack in the exterior skin of the piles. We determined this damage to be contained to the outer 20 millimetres.

Case Study #3: Park Manor East Pile Spalling
Significant “necking” in the piles within the crawlspace was observed on this structure. Physical examination and soil samples confirmed high sulphate content present in the soil. Scanning electron microscopy combined with energy-dispersive x-ray analysis revealed that concrete degradation was occurring but was attributable to physical deterioration. The uptake of sulphates created hygroscopic conditions in which the continuing growth in salts induced a form of salt scaling. However, no evidence of sulphate attack was observed in the concrete.