Concrete Mixers ~ apart from the very large output mixers most
concrete mixers in general use have a rotating drum designed to
produce a concrete without segregation of the mix.
Concreting Plant ~ the selection of concreting plant can be
considered under three activity headings †
- Mixing. 2. Transporting. 3. Placing.
Choice of Mixer ~ the factors to be taken into consideration when
selecting the type of concrete mixer required are †
Maximum output required (m^3 /hour).
Total output required (m^3 ).
Type or method of transporting the mixed concrete.
Discharge height of mixer (compatibility with transporting
method).
Concrete mixer types are generally related to their designed
output performance, therefore when the answer to the question
How much concrete can be placed in a given time period?' or alternativelyWhat mixing and placing methods are to be employed
to mix and place a certain amount of concrete in a given time
period?' has been found the actual mixer can be selected. Generally
a batch mixing time of 5 minutes per cycle or 12 batches per hour
can be assumed as a reasonable basis for assessing mixer output.
Small Batch Mixers ~ these mixers have outputs of up to 200
litres per batch with wheelbarrow transportation an hourly placing
rate of 2 to 3 m^3 can be achieved. Most small batch mixers are of
the tilting drum type. Generally these mixers are hand loaded which
makes the quality control of successive mixes difficult to regulate.
Concreting Plant