The document discusses vacuum dewatered floors (VDF), a concrete flooring technique designed to enhance strength, durability, finish, and workability by removing excess water. This method promotes a lower water/cement ratio, resulting in improved properties such as wear resistance and reduced shrinkage. While VDF offers numerous advantages, including early setting and a reduction in cracking, it has challenges like high initial costs and the need for skilled labor and specific equipment.

1. SEMINAR 2017-18
DEPARTMENT OF CIVIL ENGINEERING

2. Prepared By,
JITHIN.M.V
REG NO : 15011774
MALABAR POLYTECHNIC CAMPUS
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3.  WHAT IS VACUUM DEWATERED
FLOORS..???
• Concrete is being the most versatile of flooring material
has been in use for a long time.
• To overcome the deficiencies of concrete flooring, a system
was devised to improve the properties of such concrete
floors.
• This system was “VACUUM DEWATERED FLOORS” …
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4. • It permits to add much water for workable and easily
pourable.
• The addition of water reduces the strength of the
concrete.
• This system removes the excess water and maintain an
ideal water/cement ratio.
• This system will maintain all the properties of the
concrete.
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5.  DEFINITION FOR VACUUM
DEWATERED FLOORS..!!!
A Vacuum Dewatered Concrete Flooring method can be
defined as, “ Vacuum Dewatered Flooring ( V D F ) is a
special type of flooring technique to achieve High
strength, Longer life, Better finish and Faster work. This
type of floor is suitable for high abrasion and heavy traffic
movement.”
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6.  BENEFITS OF VACUUM DEWATERED
FLOOR…!!!
• Adopting the V D F method facilitates use of concrete
with better workability than what is normal possible.
• A lowered water/cement ratio leads to improve in each
properties of concrete like Wear Resistance, Compressive
Strength, Less Shrinkage and Minimum Water
Permeability.
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7.  BENEFITS OF VACUUM DEWATERED
FLOOR…!!!
• It will reduce the water content in the concrete by 15% -
25%, and increase the Compressive Strength.
• By lowering the W/C ratio, the tendency of shrinkage and
subsequent cracking is greatly reduced.
• Since the W/C ratio is lowered through vacuum
dewatering, concrete of high initial slump can be used
while pouring.
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8. • First patented in United States of America, nearly half a
century ago.
• Those who attracted in recent years after several
Scandinavian firms simplified the equipment enough to
make it practical for almost builders.
 HISTORY OF V D F…!!!
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9.  HISTORY OF V D F…!!!
• Vacuum Dewatering is used widely throughout Europe
today, and in Sweden.
• The method is used for 40 – 50% of all concrete floors.
• Tremix or Vacuum Dewatered Flooring is popularly known
in India.
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10.  HISTORY OF V D F…!!!
• This process was introduced in India by Aquarius
Technologies in 1987.
• In 1991 to start production of Vacuum System in India.
• It became so popular in India that almost everybody
related to concrete flooring industry.
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11.  FUNDAMENTALS FOR
DEVELOPMENT OF V D F…!!!
VALUE FOR
MONEY
LEVEL FLOOR,
HIGH FLATNESS
ACCURACY
IMPROVE WEAR
RESISTANCE
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12.  NEED OF V D F…!!!
• The mixing water added to a concrete mix exceeds the
amount of water required to fully hydrate the cement
constituent.
• The additional water functions as a lubrication medium to
allow mixing, placing and consolidation.
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13.  NEED OF V D F…!!!
• In conventional concreting practice, an important
challenge is the prevention or limiting of evaporation of
mixing water out of the freshly placed concrete.
• The uncontrolled removal of water from the concrete
matrix can result in adverse effects such as plastic
shrinkage cracking.
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14.  NEED OF V D F…!!!
• Excessive bleeding of concrete can caused for wear
resistance.
• Thus the durability and service life of the flooring
element is in question.
• In hot and windy conditions it produce quality, durable
concrete.
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15.  INSTRUMENTS USED IN V D F…!!!
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16.  BEFORE & AFTER CONDITION OF
V D F…!!!
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17.  LAYOUT OF V D F ..!!!
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18.  VACUUM DEWATERING PROCEDURE…!!!
• Preparation of sub base.
• Divide floor area into panels.
• Preparation of framework using steel channels.
• Laying down of steel bars of specified size.
• Mix design of concrete.
• Placing of concrete and compacting.
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19.  VACUUM DEWATERING PROCESS…!!!
• The vacuum dewatering process removes surplus water
present in the concrete.
• This is done using the Vacuum Equipment comprising of
Suction Mat Top Cover, Filter pads and Vacuum Pump.
• This process starts immediately after surface vibration.
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20.  VACUUM DEWATERING PROCESS…!!!
• Filter pads are placed on the fresh concrete leaving
about 4 inches of fresh concrete exposed on all sides.
• The top cover is then placed on the filter pads and rolled
out till it covers the strips of exposed concrete on all
sides.
• The top cover is then connected to the vacuum pump
through a suction hose and the pump is started.
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21.  VACUUM DEWATERING PROCESS…!!!
• Vacuum is immediately created between the filter pads
and the top cover.
• Atmospheric pressure compresses the concrete and the
surplus water is squeezed out.
• This process lowers the water content in the concrete by
15 – 25%.
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22.  VACUUM DEWATERING PROCESS…!!!
• The dewatering operation takes approximately 1.5 – 2
minutes per centimetre thickness of the floor.
• The dewatered concrete is compacted and dried to such an
extent that is possible to walk on it without leaving any foot
prints.
• This is the indication of concrete being properly dewatered
and ready for finishing.
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23.  EFFECT OF V D F METHOD…!!!
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24.  ADVANTAGES OF V D F…!!!
• Reduction in W/C ratio leads to early setting and high
strength.
• It removes the excess water of the concrete & an ideal
W/C ratio can be achieved.
• Increase in compressive strength of concrete by 40 – 70%.
• The surface hardness of the slab increase by 130%.
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25.  ADVANTAGES OF V D F…!!!
• Water absorption is reduced enormously.
• Minimum dusts.
• Level floor, high flatness accuracy.
• Minimized crack formation, shrinkage reduced by 50%.
• Improved wear resistance.
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26.  ADVANTAGES OF V D F…!!!
• Elimination or minimization of overtime.
• High and early strength, minimize damage to newly cast
floors.
• Void – free and Denser concrete.
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27.  DISADVANTAGES OF V D F…!!!
• High initial cost.
• Skilled Labour is needed.
• Need specific equipment for vacuum dewatering like
vacuum pump.
• Need power consumption during dewatering process.
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28.  APPLICATIONS OF V D F….!!!
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29.  IN INDUSTRIAL AREA SUCH AS…!!!
Hydro Power
Plants
Space
Shuttles
Workshops
Canals Cold Storage
Plants
Cooling
Towers
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30.  IN PUBLIC AREA SUCH AS…!!!
Airport
Runways
Bridges
Shoppin
g Malls
Hangers
Ports
Harbors
Railway
Platform
s
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31.  IN DEVELOPERS AREA SUCH AS…!!!
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32.  CONCLUSION…!!!
Vacuum Dewatering process is very important modern
construction work in the context of economy, facility,
modern technology and comfort. It is very useful for
special purpose projects like for the use of wear house,
parking area, industrial flooring like flooring of large area.
Nowadays V D F is used with modern techniques and
machineries.
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33. ANY QUESTIONS ???

34. Seminar 2017-18