Haiti produces some of the poorest concrete in the world. They skimp on cement and mix the materials on the ground using shovels. Following the January 2010 earthquake in Haiti, Cart-Away Concrete Systems Inc. took up the challenge to improve the quality of concrete in the country. A five-man team designed a mixer for Haiti that will improve the strength of Haitian homes.
The new mixer for Haiti is called the Concrete MD and is touted as a cure for the world’s poorest concrete. The functions of the machine are designed to fit within the culturally accepted building methods of Haiti. “They use shovels and buckets to move material, so we built a mixer that works within that system to improve the measuring and blending of the materials,” says project manager Scott Crist. The Concrete MD is a batch-fed mixer that uses two calibrated batch buckets to create a consistent blend of sand and rock in the mixing chamber.
By using four 94- pound bags of portland cement and eight dumps from each batch bucket, a Haitian construction crew can produce a half-meter of strong concrete. Consistency is what is greatly lacking in the current practice of mixing concrete on the ground with shovels. A dual-rotating auger allows the wet materials to be easily dispensed into buckets from a 6-inch door in the bottom of the mixer. The mixer is powered by a hydraulic power system that provides the torque to mix large batches every 15 minutes, yet the unit is small enough to be wheeled around the job site by a small crew.