three times until a uniform colour is obtained. Then spread the mixture and mix
with water, trying to prevent the water from dripping.
The concrete can be transported horizontally or vertically: horizontally over
longer distance and vertically to different levels or floors. Special transporting
equipment is required which must not transmit any vibration to the concrete
before it is laid, as the stones will separate from the fresh concrete.
The concrete should not be laid from heights that modify the homogeneity of the
fresh concrete.
The consolidation of the concrete consists of vibrating the fresh concrete when
it is being laid, in order to make it more resilient to external (outdoor) agents.
Concrete vibrators are used in every type of structure.
When transporting the lining it is advisable minimise the distance from mixing
area to application area. It is best to prepare the mixture on site. When placing
the concrete on the banks and at the bottom of the canal, it should be
compacted with a masonry tool to consolidate it properly.
The concrete is cured so that it slowly loses the water in the mix, reducing
dampness. Curing helps to obtain the desired resilience, as well as making the
concrete waterproof and durable. Curing is obtained by covering the concrete
with water within 12 to 18 hours of its being laid, and leaving it for at least 14
days. Much depends on the climate, temperature, and other factors.
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