By: Sarchia Khursheed

1. Sarchia Khursheed Soran University – Civil Engineering Dpt.
11 November 2015
Scientific Trip for a Concrete Plant
Ready Mixed Concrete
Ready mixed refers to concrete that is batched for delivery from a central plant
instead of being mixed on the job site. Each batch of ready-mixed concrete is
tailor-made according to the specifics of the contractor and is delivered to the
contractor in a plastic condition, usually in the cylindrical trucks often known as
"cement mixers."
Manufacturing of Concrete
Step1: Implementing the product received
Receiving facilities for aggregates make it possible for trucks to unload their goods
directly into a hopper (large funnel-like device) which feeds the product through a
conveyor belt.
The cement is delivered by tanker trucks that unload their cargo in silos via
pneumatic pipes under compressed air pressure.
Step 2: Storage of aggregates
Aggregates are stored in silos, in hoppers, or on the ground. The storage of
aggregates allows the batch plant to have several days worth of storage.
Step 3: Adjuvants (additives)
Admixtures or additives are added at the time of manufacturing to obtain fluidity,
and to accelerate or delay setting time.

2. Sarchia Khursheed Soran University – Civil Engineering Dpt.
11 November 2015
Step 4: Storage of cement
Cement is stored in silos equipped with a dust collection venting system. There
are as many silos as there are types of cement.
Step 5: Mixing
Mixing: The mixer blends the cement, sand, gravel and adjuvants supplied by the
PLC (Programmable Logic Controller). A mixer must contain up to 3 m3
.
The time and the quality of the mixing are important factors so as to produce a
good product. They are controlled by a programme.
Step 6: Control Station
The batch plants are all equipped with PLC’s to automate control production.
They allow for better selection with rigorous standards, of a formulation adapted
to the concrete ordered by clients, and according to the dosage in water
corresponding to the hygrometry of
aggregates.
Cement, sand, gravel, water and
adjuvants are dosaged (measured) and
weighed with extreme precision.
Step 7: Delivery
Fresh concrete is brought to the site via mixer-trucks with a capacity of 6 to 8 m3
,
in which it is generally mixed before delivery to clients. Delivery logistics
constitute an essential part of the process because of cement’s setting time which
is limited.

3. Sarchia Khursheed Soran University – Civil Engineering Dpt.
11 November 2015
Advantages of using Ready Mixed Concrete
 Reduction in cement consumption by 10 – 12 % due to better handling and
proper mixing. Further reduction is possible if mineral admixtures or
cementitious materials are used.
 Since ready mixed concrete (RMC) uses bulk cement instead of bagged
cement, dust pollution will be reduced and cement will be saved.
 Conservation of energy and resources because of saving of cement.
 Environment pollution is reduced due to less production of cement.
 With better durability of structure, their
overall service life increase and there is
saving in life-cycle cost.
 Quality assurance due to mechanical
handling and uniformity of processes.
 Eliminating or minimizing human error and
reduction in dependency on labour.
 General benefits like speedy work, stability
of structures, etc.
Lean concrete
Lean concrete is made with low cementitious
material content. This means that it does not have
many of the heavy, high-density rock and sand
elements that normal concrete has. Instead, it can
use a mixture of standard concrete materials,
reclaimed and crushed concrete, discarded sand
and recycled ash. This makes lean concrete very
cheap in nature and simple to make and use.