Impact of Chemical Deicers-Overview of Problems with Deicer Scaling Test Methods (PDF)

Overview of Problems with Deicer Scaling Test Methods (PDF)

Pdf Summary

The document presents an overview of the challenges and limitations associated with deicer scaling test methods, particularly focusing on the ASTM C672-12 test. ASTM C672-12 is identified as a qualitative test with variable results that does not correlate well with real-world performance. It is criticized for being too severe on supplementary cementitious materials (SCM) like fly ash and slag, often leading to unnecessary restrictions on their use. The document highlights that current test practices unfairly penalize these materials due to inadequate curing protocols before exposure to testing and environmental conditions.<br /><br />The text includes examples from field studies, such as paving slabs in Stoney Creek, Ontario, which have demonstrated good performance over time despite poor laboratory test results. The paper suggests that laboratory tests, like ASTM C672, often do not mimic the actual conditions and performance observed in the field. For example, fly ash, despite being declared suboptimal in lab tests, performed well in long-term field applications.<br /><br />The document also discusses the Quebec BNQ test, which the CSA adopted in 2014, as offering a better relationship to field performance. A new CSA method, A23.2-22C, is proposed to address the limitations of the older tests and better reflect field conditions. It involves factors like no final finishing, extended curing times, and side insulation to minimize lateral freezing.<br /><br />In conclusion, the paper argues for a shift from the ASTM C672 test to more accurate and representative methods like the new CSA tests. These new methodologies are hoped to provide more reliable predictions about the material's performance concerning deicer salt scaling and thus inform better concrete design and material utilization decisions.

Keywords

deicer scaling test

ASTM C672-12

supplementary cementitious materials

fly ash

slag

field performance

Quebec BNQ test

CSA A23.2-22C

curing protocols

concrete design