A Concrete Mixer for Helping Haiti

Helping Haiti to produce better concrete

Haiti produces some of the poorest concrete in the world. Their poverty causes them to skimp on cement and then mix the materials on the ground using shovels. These actions have resulted in over 20-million cubic yards of rubble and hundreds of thousands of deaths.

Following the January 2010 earthquake, a Oregon machinery company took up the challenge to improve the quality of concrete in Haiti. A five-man team from Cart-Away Concrete Systems designed a mixer for Haiti that will improve the strength of Haitian homes. “The slowdown in US construction provided us the time to devote our efforts to this problem in Haiti,” stated Scott Crist, the Project Manager. “The silver lining to our economic problems is that we could make the rebuilding efforts in Haiti more sustainable.”

The new mixer for Haiti is called the Concrete MD and is touted as the prescription to cure the world 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,” continued 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 94lb bags of Portland cement and eight dumps from each batch bucket, a Haitian construction crew can produce ½ meter of strong concrete, over and over again. This consistency is what is greatly lacking in the current practice of mixing concrete on the ground with shovels.

“We used an auger design that we first produced in the 1990’s. This type of mixing action will allow crews to produce both ready-mix concrete and mortar with the same machine,” added Tom Vail, the President of Cart-Away. This dual functionality is important in Haiti because the traditional building process includes concrete floors and mortared block walls to create a home.

The dual-rotating auger allows the wet materials to be easily dispensed into buckets from a 6-inch door in the bottom of the mixer. Buckets are then used to carry the materials to the forms using a chain of workers. 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.

Building unique mixers is not new to the Cart-Away team. They have manufactured mixers for the US and Canadian rental markets for the past 17 years, so the Concrete MD is robust enough to withstand the remote construction environment of Haiti. “The solution to rebuilding a strong Haiti is a decentralized concrete production system, where small mixers are working all around the island in unison,” added Vail. “The organizations who have committed money to this effort can greatly improve the quality and sustainability of construction by providing better tools and letting the Haitian’s work.”

The fact is that, in Haiti there are thousands of skilled cement-masons who need work and are highly motivated to build stronger homes this time around. Many of the million-plus homeless know that it was poor quality concrete that crushed family and friends and they want better concrete. By providing better mixing methods and teaching the use of consistent recipes, they will achieve safer living conditions in the future.

With the reputation for producing the poorest concrete in the world, Haiti can now change course and use the Concrete MD as the prescription for stronger concrete.
More details concerning the problems with Haiti’s concrete production methods and the new mixer can be found at www.theconcretemd.com

About cementtrust

I am a director with Cement Trust and passionate about improving cement-based production in the poorest nations of the world.
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2 Responses to A Concrete Mixer for Helping Haiti

  1. fat chance says:

    It’s unfortunate you want those who would leave comments to log-in using various security compromised methods. I will not post comments from facebook, tweeter, or wordpress, nor do I have accounts in any of those places. However, I will attempt to leave this comment with a throw-away email. Rant over, I offer the following:

    Excellent mixer design, that is the solution I was looking for in pondering aloud what it would take to create very basic housing tenements in blocks of 100 units. Each unit would be 12’x20′ with 50 along the “street” face, with two units along the “alley” face, only a single story design, but modular in nature. Each block of units (100) would require approximately 15 cu.yd of 3500psi concrete and 15 cu.yd. mortar, along with 15,000 standard weight CMU’s. It strikes me as very odd with all the 15’s, and of course there is about 10% overage built into all the estimates, but I digress. Quickly expanding out because I’ve got to get back to work. If “slums” were created, 1mi square, with “blocks” of 600feetx40feet, with 25′ “streets” and 10′ alleys. It would take about 10million CMU’s, 10,000 cu.yd. concrete, 10,000 cu.yd mortar, 50,000feet of 30″ PVC sewer collector pipe, 65,000ft of 10″ water main. And it would house 65,000 familys of up to 5 people, 325,000 people total.

    Quick rough numbers come to 44million, or about … wait for it … $133 per person. Not a bad deal at all if I say so myself. I know there is going to be maybe another million or so for rebar, and roofing, but why can’t anyone in the government, or those ricockulous “aid” organizations figure that out? And wait, there’s more.

    You’ve got to feed those 325,000 people breakfast lunch and dinner until construction is complete? Let’s say six months (material dependent). That’s about 182 million meals. These people don’t need nutritious food at this point, they need calories for their bodies to burn, plain and simple. Delicious Bar S hotdogs can be bought at a grocery store for $0.25 each, buns for $0.13, bag of chips for $0.20, bottle of water $0.25. Or about $152million.

    So for less than the cost of a propaganda-filled hollywood movie, I could rebuild homes and feed more than half of those whose slums were destroyed in the hurricane. $200 mil.

    • cementtrust says:

      Fat Chance,

      Thanks for sharing your “pondering” on our blog…
      We hope that all of the creative ideas that are suggest for building homes will be explored and that some will find good results.
      Good luck with your plans…


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