Sulfate Attack on Concrete-Development of Test Methods to Address Various Mechanisms of Sulfate Attack (Recorded presentation)

Development of Test Methods to Address Various Mechanisms of Sulfate Attack (Recorded presentation)

Video Transcription

Video Summary

The presentation offered insights into mechanisms of external sulfate attacks on concrete, chaired by an expert in the field. The speaker elaborated on various types of sulfate attacks, including chemical interactions with cement (such as the attack on C3A and thomasite formation), and physical attacks involving salt crystallization. Emphasis was placed on understanding the lack of standard sulfate resistance tests for concrete and the reliance on other measures like water-cement ratio as proxies for durability. The discussion included laboratory tests like ASTM C1012 and ASTM 452, which assess concrete's sulfate resistance in controlled conditions. The effectiveness of supplementary cementitious materials such as slag and fly ash in mitigating damage was highlighted. Moreover, the importance of concrete's maturity before exposure to sulfates was underlined for better resistance. The presentation concluded by addressing recommendations for testing and reiterated the need for comprehensive strategies to manage sulfate-related deterioration in concrete structures.

Keywords

sulfate attacks

concrete durability

supplementary cementitious materials

ASTM C1012

chemical interactions

sulfate resistance tests