Ward R. Malisch Concrete Construction Symposium (Part 1)-After Two Hundred Years of Estimating Evaporation, It Is Still a Mystery (Recorded presentation)

After Two Hundred Years of Estimating Evaporation, It Is Still a Mystery (Recorded presentation)

Video Transcription

Video Summary

In this presentation, Ken Hover discusses the complexities of predicting evaporation, particularly from concrete surfaces, drawing on his extensive experience and research in the field. He highlights that the original equation for anticipating evaporation, dating back 215 years, was modified in the 1950s for concrete applications without significant adjustments, which poses several challenges. Hover explains that the precision of these predictions often varies, with a potential 40% error rate under strictly controlled conditions, and up to 200% error when using less rigorous methods, such as weather records or apps. He stresses the necessity of taking on-site measurements according to specific guidelines for accurate results. Hover also underscores the importance of understanding the relationship between evaporation rates and concrete bleeding, which impacts concrete's hydration, strength, and overall durability. To improve current practices, Hover proposes establishing standardized protocols for measurements and accounting for environmental and material variabilities.

Keywords

evaporation prediction

concrete surfaces

measurement guidelines

hydration and strength

standardized protocols

environmental variability