"Minimal to Zero Cracking?" Really?

So I need to update the Pacific North West on something. I've been hearing about the success of E5 nano silica admixture being used in Indiana and the surrounding states. Indiana DOT (INDOT) has even produced a video https://www.youtube.com/watch?v=pNZT_QcP2jw documenting the "minimal to zero cracking" they experienced using E5 on bridge decks - and they've placed well over 40 bridge decks with this now I can't keep up. Minimizing cracking is just one of the benefits of good concrete curing. I've been in the concrete industry since I was 15 years old - I'm now 42. I know concrete, I know it cracks and NOTHING can completely eliminate all cracking. But there are many different types of cracking. The most common is caused by drying shrinkage caused by improper curing because our industry simply doesn't have the time or doesn't have it in the schedule to cure concrete properly. Concrete cures properly when there is sufficient time, temperature, and moisture present to completely hydrate the cement. Even if you wet cure, the curing stops as soon as the concrete dries out.

The ideal solution from the industry's standpoint would be to put the cure in the mix, so that you don't have spray anything on the surface or keep it wet which isn't always practical or possible. If DOT's are publicly coming out and stating that E5 internal curing works, and there is MINIMAL to ZERO CRACKING that has got to get our attention. Drive around and see all the cracks in our infrastructures everywhere, not just cracks, but scaling, delamination*, ASR, etc. Our concrete needs to be cured better obviously. It's slowly falling apart. I had to try this myself. I recently placed a 3000 SF SOG with radiant heat tubing so we couldn't saw cut it. It has a lot of re-entrant corners that would normally crack like crazy. E5 says it binds water molecules to the cement for indefinite curing - OK, I had to prove it to myself. Lab tests are great - but when you see its effect in the real world with the atmospheric conditions concrete has to endure while curing, and if it works in the hot weather we've just experienced, then I've got something.

The slab was placed by Rod Smith with Smith Art Concrete. Rod never saw a slab that didn't have any bleed water before! That's right - think about it - if there is no visible bleed water that means there isn't a capillary or void system created by bleed water exiting the slab. The water is being held in for continual hydration. And you don't have a capillary system that leaves the concrete open to attack. You've just solved one of the biggest problems the entire concrete industry has been perplexed with for hundreds of years.

Back to the slab! I put rebar in the re-entrant corners. I used the E5X system with fiber and had Rod's guys use the E5 Catalyst as a finishing aid. The Catalyst is supposed to accelerate the hydration reaction at the surface to densify the surface allowing faster placement of flooring/polishing etc. I started polishing in 2 days after placement. No sand or aggregate pitting noted at all. I wet ground with 50 grit using the E5 cutting compound. I counted 4 tiny cracks coming off inside corners, only inches long. No cracks in the middle of the slab, no craze cracking, no spider cracking, no plastic shrinkage cracking. Extremely hard and durable surface. And I saved the client over a month on schedule. Tell your ready mix producer you want E5! #nanosilica #E5 #concrete #polishing #curing #readymix #sustainability #structuralengineers #architects #concretefinishers #concreteconstruction #concretelife #constructionindustry #engineering #architecture #transportation #concreteprotection #greenbuilding #nanotechnology #concreteproduction #concreteproducers #carbonreduction #carbonneutral #sustainableconcrete (*E5 eliminates bleed water so it prevents delamination caused by finishing before the bleed water evaporates)