IT IS ONE OF THE TYPE OF CONCRETE

1. A project on

2.  Introduction
 Need for vacuum concrete
 Equipments
 Applications
 Advantages
 Disadvantages

3.  Vacuum concrete is the type of concrete in
which the excess water is removed for
improving concrete strength.
 It was first invented by billner in united
states in 1935.
 Reducing the final water –cement ratio of
concrete before setting to control strength
and other properties of concrete.

4.  The chemical reaction of cement with water
requires a water –cement ratio of less
thsan0.38.
 But it is always taken more than 0.38.
 Workability is also important for concrete.
 Workability and high strength don't go
together as their requirements are
contradictory to each other.
 Vacuum concrete is the effective technique
used to overcome this contradiction of
opposite requirements of workability and
high strength.

5.  Vacuum pump with hose pipe

9.  With the help of screen vibrator the surface
is vibrated .
 Vacuum pump is small but strong pump of
5to 10HP.
 The mats are placed over fine filter pads .
 Water from concrete is vacuum and stored in
separator .
 About 3% reduction in concrete layer depth
takes place .
 By the use of power trowel and power floater
the surface is given a hard and smooth finish.

11.  Industrials floor sheds like cold storage.
 Hydro power plant .
 Bridges ports and harbor .
 Cooling tower.

12.  Increase of final strength of concrete by
about 25%.
 Sufficient decrease in permeability of
concrete.
 High density concrete.
 Increase of about 20% bond strength of
concrete.
 Appreciable reduction of time for final
finishing .
 Early removal of wall forms .
 Increase in durability.

13.  High initial cost .
 Need trained labor .
 Need specific equipments .
 Need power consumption .
 The porosity of concrete allows water /oil
and grease to seep through ,consequently
weakening the concrete.

14.  Good quality of floors and pavements can be
obtained
 The compressive strength can be increased
by 25-45%.
 Durability of the floor can be increased m.
 15-25% oil water can be extracted out.