What happens when the concrete industry’s “wonder dust” meets its high-tech rival?

In this episode of the Concrete Logic Podcast, host Seth Tandett brings back Dan McCoy and Dr. Jon Belkowitz to challenge everything we thought we knew about silica fume. From bridge deck overlays that crack like eggshells to the real CO₂ math no one wants to talk about, the guys separate hype from chemistry and ask the only question that matters: What are we really asking this concrete to do?


What You’ll Learn
• What is silica fume really — and how did it end up in our concrete?
• How does colloidal silica change the way concrete performs in the field?
• Why bridge deck overlays using silica fume often fail before their time.
• How mix design mistakes turn silica fume into a “volatile” material.
• Why colloidal silica can actually cost less than silica fume.
• What’s the environmental truth behind “green” cement substitutes?
• Why performance specifications—not recipes—should drive concrete design.
• The one ASTM document every purchaser should actually read.


Chapters
00:00 Introduction and Guest Introductions
01:36 Understanding Silica Fume
05:11 Colloidal Silica vs. Silica Fume
13:38 Practical Applications and Challenges
18:34 Cost Analysis and Environmental Impact
32:52 Exploring Concrete Associations and Data Sources
33:07 Understanding CO₂ Emissions in Concrete Materials
34:34 Debating Environmental Impact of Fly Ash
36:03 The Role of Coal in Concrete Production
38:23 Analyzing Silica Fume vs. Colloidal Silica
40:10 Cost and Benefits of Silica in Concrete
41:23 Challenges in Using Silica Fume
43:03 Evaluating Cost Structures of Concrete Materials
45:22 Understanding Concrete Specifications and Purchaser Requirements
46:56 Concluding Thoughts on Concrete Practices



Guest Info
Dan McCoy, P.E. — R.L. McCoy, Inc.
Email: [email protected]
LinkedIn: https://www.linkedin.com/in/dan-mccoy-48507730/
Website: https://www.rlmccoy.com

Dr. Jon Belkowitz, Ph.D., P.E. — Director of Research, Intelligent Concrete
Email: [email protected]
LinkedIn: https://www.linkedin.com/in/jon-belkowitz-phd-pe-53494719/
Website: https://intelligent-concrete.com



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Podcast Partners

Intelligent Concrete
At Intelligent Concrete, we combine lab precision with field expertise to help you understand what your concrete is telling you. Our services include mix troubleshooting, forensic and petrographic testing, performance-based specification and admixture development, and training for engineers, contractors, and producers. Whether you’re chasing consistency, durability, or answers after a failure, Intelligent Concrete delivers the data and insight to solve problems and improve performance.
Learn more: https://www.concretelogicpodcast.com/intelligent-concrete

Credits
Producers: Jodi Tandett & Concrete Logic Media
Music by Mike Dunton — https://www.mdunton.com



Connectivity
Host: Seth Tandett — Concrete Visionary & Host of The #1 Concrete Podcast
LinkedIn: https://www.linkedin.com/in/sethtandett
YouTube: https://www.youtube.com/@concretelogicpodcast
Website: https://www.concretelogicpodcast.com


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