Chloride Limits and Thresholds for Concrete: Perspectives in Laboratory Testing and Modeling Techniques-Confusion on Chloride Limits in Specifications that Challenge the Industry (Recorded presentation)

Confusion on Chloride Limits in Specifications that Challenge the Industry (Recorded presentation)

Video Transcription

Video Summary

The presentation provides an industry perspective on the impact of chloride limits on concrete standards. Chloride is crucial in corrosion, requiring moisture and oxygen to affect reinforcing steel. It's noted that submerged steel doesn't corrode due to lack of oxygen, and typically, steel is passivated in concrete. ACI standards focus on chloride types: internal from materials, and external from environmental exposure. Internal chlorides, when limited, control carbonation, primarily a European concern. Variability in threshold concentration makes setting definite limits challenging, leading to different interpretations in codes. A study aims to correlate calculated and water-soluble chlorides, assessing their contribution via materials like aggregates and mixing water, noting wash water must meet ASTM standards. ASTM tests and guidelines govern chloride evaluations, but industry compliance varies, with stress on calculating over testing due to high costs. Uniformity is hindered by differences between ACI standards, affecting application and cost implications of testing.

Keywords

chloride limits

concrete standards

corrosion

ACI standards

ASTM guidelines