Transportation methods of concrete

1. TRANSPORTATION OF
CONCRETE
1
Richu George Varghese
Assistant Professor
Mangalam College of Engineering and Technology

2. Introduction
◻ Transferring of concrete from mixing plant to
construction site
◻ Important activity in the production of concrete.
◻ Time taken in transit should be a design parameter
as it depends on
1. Initial setting time
2. Requirement of workability at the destination.
◻ Method of transportation adopted at site should be
decided in advance so that suitable admixtures can
be decided
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3. Precautions and Objective
◻ Precautions:
□ Transportation of concrete tends to produce
segregation and loss of slump, if the distance is long
□ Movement of hand trolley or truck on rough road
surface makes vibration
□ Results in deposition of heavy aggregates at bottom of
truck
□ Water and cement slurry comes on top
◻ Main objective – ensure that water cement ratio,
slump or consistency, air content and homogeneity
are not modified from their intended states.
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◻ Goals :
□ to prevent segregation
□ to not reduce the workability of the mix.
◻ General rule of thumb,
□ Thirty to sixty minutes - small jobs
□ At ready-mix plant, concrete should be discharged
from a truck mixer or agitator truck within two hours.
□ If non-agitating transporting equipment is used, this
time is reduced to one hour.

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Types of
transportation
Vertical Horizontal

6. Methods of transportation of concrete
◻ Mortar pan
◻ Wheel barrow, hand cart
◻ Crane, bucket and rope way
◻ Truck mixer and dumpers
◻ Belt conveyors
◻ Chute
◻ Skip and hoist
◻ Transit mixer
◻ Pump and pipe line
◻ Helicopter
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7. Mortar pan
◻ Labour intensive method
◻ Generally used for small works
◻ No chances of segregation of concrete
◻ Greater surface area of concrete exposed to sun,
drying conditions great loss of water
particularly in hot weather
◻ Mortar pan must be wetted to start with and must
be kept clean
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9. Crane , bucket and rope way
◻ Crane bucket and ropeway are used for transporting
concrete above ground level
◻ Crane:
□ Main consideration in selecting the crane is height and
radius of operation
□ Fast and versatile and allows movement in all
directions
□ Depending upon the site, cranes may be - derrik crane,
tower crane, crawler mounted, wheel mounted, or
hydraulic crane
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11. Bucket
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□ Square or circular
□ Needs the aid of a crane, cableway, or hoist so that it
can be moved horizontally or vertically.
□ Types:
■ Opening at bottom: door opened and released
■ Opening at top: discharged by tilting or using forced action
□ Size – 0.5 m^3

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13. Ropeway
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•Suitable for works in valley, over high piers and long dam sites.
•Excessive free fall of concrete should be avoided to minimize
segregation
•Concrete is transported in a container with help of rope and
pulleys

14. Belt conveyors
◻ It has limited application due to
□ Chances of segregation on steep slopes, roller points
and changes in direction of belt
□ Over-exposure of concrete to environment.
◻ Used for continuous operations
◻ Low slump concrete - for slower moving belts and higher
slump concrete - faster moving belts
◻ 100 - 350 cubic yards per hour
◻ Concrete mix is spread very thinly on the conveyor and is
susceptible to loss of moisture during hot weather
conditions.
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◻ used in horizontal directions, but can be moved in
the vertical direction (i.e. up to 35o) with some
adjustments to the conveyors.

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17. Chute
◻ Used for concreting in deep locations.
◻ Care should be taken that slope should not be flatter
than 1V:2.5H, otherwise concrete will not slide down.
◻ Workability should not be changed to suit the delivery
by chute.
◻ Technically it is not a very good method but it is
extensively used in the field.
◻ Should only be used in short lengths since concrete
becomes more susceptible to segregation and drying
out.
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◻ When they are used, it is very important that the
concrete mix is workable and cohesive, hence
should be re-mixed at the lower end by passing
down through a funnel-shaped pipe or drop chute.

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20. Helicopter
◻ more economical in the hilly regions like high
mountains. Very fastly one can transport concrete
to the construction site within mins.
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21. PNEUMATIC GUNS
(SHOTCRETE)
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□ Used where concrete is to be placed in difficult
locations and where thin sections and large areas
are needed

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23. TREMIE
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□ In the Tremie Concrete method, concrete is placed below
water level through a pipe, the lower end of which is kept
immersed in fresh concrete so that the rising concrete from
the bottom displaces the water without washing out the
cement content.
□ The tremie concrete method is often used in bridges that span
bodies of water. In this case, the pier footing is supported by a
tremie. Tremie pipes are also used to pour the concrete in
slurry walls.

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25. Use of technology
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◻ Using live monitoring and remote database one can
transport concrete with ease.
◻ GPS is installed in the truck mixer and along with
the live monitoring system and remote database the
truck GPS are interconnected. Thus making the
transport more feasible.