19 June 2001
CPM-3: CAST-IN-PLACE CONCRETE
Description: Placing conventional concrete mix with a concrete mixer truck,
chute, bucket, wheel barrows, concrete carts, or shovels.
Uses: Use in all repairs where the quantity of concrete required is too large for
hand placement, and where special placement methods CPM-4 through CPM-7
are not required. Control of the concrete mix and strength of the completed repair
is much better than with any other methods. Should be used when:
The hole/cavity extends through the concrete section.
The cavity in un-reinforced concrete is larger than 900 cm2 (139 in2) in area
and over 10 cm (4 inches) deep.
The cavity in reinforced concrete is over 450 cm2 (69 in2) in area and
deeper than the reinforcing steel.
Major concerns are quality of the mix, good bonding to old surfaces, keeping a
low water-cement ratio, and proper curing.
a. Temperature shall be over 4.5C (40F) during placement.
b. Concrete settles after placement, therefore, proper consolidation is
Preparation: See concrete repair (CR) procedure CR-3.
a. Delay several days after demolition of old, deteriorated concrete to
confirm the soundness of remaining concrete and excavated surfaces.
b. Check forms for tightness and stability.
c. Ensure that old surfaces are cleaned before repairs
d. Ensure that reinforcing steel is cleaned of rust and scale and
exposed at least 2.5 cm (1 inch) all around.
a sand-cement grout will suffice. See CR-3 for more
Concrete Mix: Give particular attention to:
a. Take careful measures to minimize drying shrinkage by selecting a
material mix design with a maximum allowable shortage of 0.05 percent and