At the delivery site the concrete transported by
truck-mixers is hauled horizontally and/or vertically for final placing into
the forms.
A small quantity of concrete can be hauled at the site
by using wheelbarrows, chutes, portable belt-conveyors or hoisting units. But haulage
of a large quantity of concrete needs a crane and bucket arrangement. Or the
latest trend is to use concrete pumps.
Concrete buckets come in varying sizes. These are
attached to hooks of suitable cranes for lifting concrete at desired heights.
These buckets have a bottom gate which can be released manually for discharging
concrete at the desired location. Concrete buckets can also be tied up with
fork-lifts for moving concrete over short horizontal distances.
Concrete Bucket Use
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Concrete Bucket
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Concrete pumps provide the most acceptable, easy, and
quick method of placing concreting. These are commonly used in the
industrialized countries. Concrete pumps can be broadly divided into two
categories, viz. truck-mounted mobile pumps and trailer-mounted stationary
pumps.
Use of Truck-Mounted Mobile Pump
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Truck-Mounted Mobile Pump
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Truck-mounted mobile pumps have the ability to deliver
concrete up to 120 m3/h at a height above 40 meters. But it creates
handling logistic difficulties. Usually mobile concrete pumps operate in the
range of 35-45 m3/h or even less. The pumping distance and the price
of the pump depends upon the boom length of the pump. For planning purposes,
the vertical distance at which a concrete pump can deliver concrete with its
boom can be taken as 2/3 of the boom length with remaining boom length being used
for placing concrete horizontally. The mobile concrete pumps are frequently
moved from place to place. They can also be used in the stationary mode of
delivering concrete, horizontally or vertically up to designed distances, by
fixing and suitably anchoring extension pipes.
Stationary Concrete Pump
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Use of Concrete Pump
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The stationary concrete pumps are mounted on trailers
and are moved occasionally. There are positioned in the vicinity of the place
where concrete is to be delivered by pumping concrete vertically or
horizontally. The pump is connected to the delivery site by a pipeline through
horizontal and vertical pumping distance and the nature of bends in the pipeline.
These details can be found in the manual of the concrete pump.
The truck-mounted mobile concrete pumps are preferred
to trailer-mounted stationery pumps due to their mobility, flexibility, ease of
maintenance and higher pumping capacity. Gradually, the stationary pumps,
though cheaper for certain work situations, are being replaced by the
truck-mounted mobile concrete pumps.
