Cool as a Cucumber

It’s summertime. The sun is out, you have concrete orders coming in, business is good.

THE PROBLEM:

With summer comes high temperatures, dry air, and faster concrete set times. There are plenty of ways people choose to combat this across all types of concrete delivery, but in this article we are going to focus on the best way for the volumetric concrete industry specifically. Using the correct admixtures, high-quality materials, and clean water are all great plans to set yourself up for success. Ensuring your machine is calibrated correctly and in good mechanical condition will of course allow you to operate without worry. What happens, however, if it’s just too hot and dry out there? Your concrete is flash setting and false setting, it’s getting away from the finishing crew, and nobody’s happy. Your track record for consistent, fresh concrete is feeling the pressure.

THE SOLUTION:

In short  – the answer is water – specifically in the context of the aggregates you plan to use. The technical term for this method is “Evaporative Cooling”, which is precisely how it works. Keeping your aggregates moist also keeps them cool, due to the natural process that water vaporization creates. This is the most cost-effective and universal way to keep your concrete from “going off” too early, which keeps the crew and finishers happy, ultimately creating less problems down the road. Keeping your aggregates cool before mixing them greatly reduces chances of a flash set, and also keeps false set to a minimum. Not only that, but thermal cracking and excessive bleed can also be reduced with an increase in strength, because the aggregates have had plenty of time to soak up the moisture they need for an optimal chemical reaction.

HOW TO DO IT:

There are a few different tips and tricks for the most efficient way to keep cool. Keeping the ingredients in a covered canopy is ideal, but adding water to them as needed is key.

The most common method is to use an overhead sprinkler system. This can be as simple as a manual common sprinkler system to a fully automated custom setup. The tricky part is finding a good balance between cooling aggregates without soaking it too much. Moisture meters are available to probe the aggregates so you can find a happy medium to know how much water you need. Commercial sprinkler setups are available from companies like AutoJet® or TORO Irrigation, usually custom setups depending on your needs. You’ll want wide range, full-cone style nozzles and lots of water pressure!

Pro tip – starting early in the morning while it’s still dark will allow the whole pile to soak, meaning you lose less water as quickly, which is more efficient.

If you any need help or advice for volumetric concrete operations, Bay-Lynx experts are on standby to answer your questions!