Concrete Projects

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Concrete Projects
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Form preparation

• A. Oil the form faces that come in contact with
  the concrete.
• B. Thoroughly soak the sub-base and forms with
  water before the concrete is placed.
• C. The reinforcing steel should be cut to the
  correct size (length) and placed prior to the
  arrival of the ready-mix truck, or after mixing
  in portable mixer.

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General preparation

• A. Be sure the site is ready and waiting when
  the mix truck arrives, because you may be
  charged for any time delays.
• B. Have adequate labor present when the
  ready-mix truck arrives.
• C. Plan your job so the ready-mix truck can get
  as near to the site as possible.

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Placing concrete

• A. Deposit the concrete in level layers,
  consolidating it just enough to make the
  concrete settle thoroughly and produce a dense
  mass.
• B. Vibrate the concrete to make sure all the
  voids are filled and this will ensure a smooth,
  dense surface when the form is removed.
• C. Concrete should be placed between the forms as
  nearly as practical to its final position.
• D. Spade the concrete as it goes into the forms
  and next to the forms to eliminate voids or
  honeycombing at the sides.
• E. Overworked concrete in the plastic form will
  allow too much water and fine materials to be
  brought to the surface. This will lead to
  scaling or dusting of the surface.
• F. Use extra care in working materials into
  corners and angles of forms and around the
  reinforcing steel.

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Placing concrete

• G. Do not dump the concrete in separate piles and
  then level it by working the piles together.
• H. Do not use a soupy mix and hope to float the
  concrete into its final position. Segregation
  occurs because the mortar tends to flow ahead of
  the coarser aggregate.
• I. A good rule of thumb is, Agood concrete is
  placed, not poured._at_
• J. After concrete is placed use a straight edge
  to level and compact the surface.
• K Concrete should be placed 30 to 45 minutes from
  the time water has been added to the mix.

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Tools need to place concrete

• A. Shovel
• B. Spade
• C. Rake
• D. Straight edge

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