Over the past few years, the concrete and construction industry has seen a significant shortage of materials, not the least of which is fly ash. Fly ash is a popular material for concrete because it increases the overall strength and durability of the mix while reducing water and cement requirements. And because fly ash is a byproduct of coal-powered electric plants, it is a more cost-effective material than cement. Unfortunately, the demand for fly ash is outpacing the available supply – leaving the concrete industry scratching our heads trying to find an acceptable alternative.
So why is there a shortage?
It is difficult to nail down the shortage of fly ash to just one thing. There are, in fact, many different factors that are contributing to this problem. Current events such as the pandemic, unusually rough weather patterns, and a labor shortage are all things to consider when pondering the state of fly ash availability.
Following the pandemic, as the economy started to bounce back, the demand for winter concrete projects was unusually high. This meant that cement, concrete, and fly ash facilities could not build up an inventory of materials. And what materials are available are often stuck at the manufacturing or storage facility due to there not being enough truck drivers to transport the materials to the concrete plant. Finally, the transition from coal-powered energy has impacted the amount of available fly ash.
What are the Challenges?
Regardless of the reasons, the fly ash shortage impacts the concrete industry – particularly concrete pumpers and precast concrete workers. Fly ash is a common material used to improve the pumpability of concrete mixes, particularly those with coarse aggregates. The fly ash in the mix acts like ball bearings to keep the concrete moving smoothly through the boom. Without the fly ash, some pumpers request additional sand to help with the pumpability, but this can affect the strength of the concrete.
Precast concrete workers rely on fly ash to create durable concrete that won’t break as it is stored or transported. Also, because fly ash is such fine material, it lowers the risk of voids in the concrete, making the concrete even stronger and improving the overall appearance of the mix.
So What is the Solution?
The good news is that there is a simple solution that can help mitigate the concerns brought on by a limited supply of fly ash. That solution is admixtures. Specifically, the admixtures that help solve the problems facing concrete pumpers and precast workers are pumping aids and superplasticizers. Pumping aids, such as Fritz-Pak’s Slick-Pak II, are specially formulated to be that ball-bearing material in the mix, without affecting the water-cement ratio or changing the strength of the concrete. Superplasticizers improve the flow of the concrete and the strength without additional material and can lower either the water or cement requirements. And if you’re looking for a delayed set time, our Supercizer 2 and Supercizer 7 are premium superplasticizers with a built-in delay set.
Find Out More
If you’re looking for more information about using a pumping aid or a superplasticizer in your mix that can help overcome the challenges presented by the low supply of fly ash, visit our online store at fritzpak.com/store. Don’t forget to follow us on social media to learn more about how products can improve your concrete.