The demand for high-performance concrete has escalated to new heights the last 10 years. Producers are constantly facing new challenges to develop mix designs that will perform wondrous feats that were unheard of just a decade ago.
Low water/cement ratio flowable mixes, self-consolidating concrete, pervious concrete, high early-strengths for highway repair, and overcoming alkali-silica reactivity (ASR) problems are just a few examples, and the list goes on. To develop and improve these new innovations, the concrete producer is confronted with disruptions to the business of the day. These procedures upset the flow of daily production. It is often difficult to schedule necessary tests to verify the results required for the mixes or project.
Brett Admixtures, of Albertville, Minn., and the distributor for Euclid Chemical, has put an end to that. They literally put the show on the road. After months of development, they created a mobile lab equipped with all of the state-of-the-art equipment necessary to completely design, prove, test, and quantify just about any mix design scenario thrown at them.
“We start from scratch when we begin a project request,” says Davin Maki, the operator of this rolling laboratory. “We don't assume anything. We start with a producer's aggregates and build the mix around what they have available. The coarse and fine aggregates are sieved and documented before we proceed.”
Scott Baril, director of technical services for Brett, has equipped the trailer with Mix Master, a mix design software that simulates the results of the trial, based on the performance of the ingredients. Mix Master takes into account the properties of all of the components of the mix and accurately predicts the probable outcome.
Once the design has been completed, the technician gathers adequate quantities of the producers' raw materials and begins the trial batch process. The trailer is fully equipped with every type of admixture imaginable: its own mixer, test cylinders, curing tank, air pot, compression machine, flow tables, and a microwave for proving water/cement ratios.
On the spot analysis
The mix can be analyzed and adjusted on the spot, and changes can be made and documented for future reference. Once cast, the trial mixes are cured and test cylinders broken in hourly increments if required. Data is processed immediately and any necessary changes are made to ensure the producer has accurate results before putting a mix into production.
Sioux Falls, S.D.-based Winter Inc. benefited from the mobile lab's convenience. Time was of the essence to supply a proven basement wall mix design that would attain 2500 psi in four hours. This was the requirement for the “Extreme Makeover” tevevision series.
Mixes were designed and batched at the Sioux Falls plant in the mobile lab. Results for the “Extreme Makeover” project were in by 9 o'clock that same evening. They were also awarded a contract to supply 40,000 cubic yards for a wind generator project requiring 5000 psi in 14 days. Accuracy for a project of this size is not left to guesswork. The mobile lab again produced the results.
“From a producer's point of view, it's the all-in-one process,” says Jeff Mataia, Winter's general manager. “I've worked in most of the U.S. markets, including Hawaii, for 30-plus years. This technology didn't exist until now. We talked about the mixes, which were designed right here on their laptop, batched, and cylinders broken, all in the same day. Normally you have to go through several channels, and are lucky to see results in a week.”