thin shell cement deck

Discussion in 'Shop Talk' started by gobug, Aug 6, 2004.

  1. gobug

    gobug Well-Known Member Supporter

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    Last weekend I built a thin shell 5'x13' cement deck.

    I had a wooden frame in place already. I attached 6x6 welded concrete reinforcement wire to the top using "U" nails.

    Then I stapled two layers (running perpendicular to each other) of window screen over the wire.

    I mixed a slurry of portland cement, grade c fly ash, and a mixture of water and white bonding agent. I used a plastic putty knife to scrape the slurry through the screen.

    I let the screen dry about an hour. It had a texture like canvas and was not quite as brittle as fiberglass.

    I covered the screen with a layer of expanded metal. I did not attach it. The metal wrapped around the step and covered the whole top surface.

    Then, I mixed 1 portland 2 sand and 1/2 flyash plus 1/10 volcanic ash with a plasticizer and parged it onto the screen and metal lathe.

    The decking surface is about 1/2 inch thick. Its waterproof and has a little flex.

    The whole surface probably weighs about 300 pounds. The materials, not including the framework cost about $50. I didn't take pictures of the construction sequence, but I will post a picture of the deck soon. I plan to put on one more layer of lathe and cement.
     
  2. gobug

    gobug Well-Known Member Supporter

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  3. Blu3duk

    Blu3duk Well-Known Member

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    nice pic, did the flyash make the color a dark purple or did you use a colored sand?

    around Lyons CO they use the ground remnants from the flagstone quarries to get a red color which i found refreshing while living there a few years back..... to expensive to hual it this far just to color the concrete though!

    I lived above Lyons in a quarry ob beach hill, and a friend bought a quarry on Nolan road the nexy year after i left..... i kinda liked it there except for the yuppies.

    William
     
  4. gobug

    gobug Well-Known Member Supporter

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    I colored the cement with a mix of powdered colors for concrete. They were left overs of samples I bought to try. Unfortunately, I thought one mixer load would cover it. The second load was a different color. For the final coat, I will be careful to measure accurately so the color is uniform. The flyash partly acts as an accelerant, but the real benefit is that it makes the finished product more than twice as strong. The flyash is a yellowish color, a little lighter than cornmeal. It does affect color, but not drastically.