1. Grouting is a process of injecting fluid materials like cement into subsurface soils or rocks to fill pores and fissures. 2. There are different types of grouting materials and methods depending on the permeability and structure of the soil or rock. 3. Grouting is used for ground improvement on construction projects, fixing anchors, repairing defects, and other applications.

1. GROUTING

2. GROUTING
• Grouting is a process of ground improvement attained by
injecting fluid like
• material into subsurface soil or rock.
• Grouting is the injection specially formulated cement of stable
suspensions
• or liquid into pores, fissures or voids, or the jetting of cement
mixtures at
• high flow rate and pressure into the soil to create soil-
cement to increase
• the strength.

3. • Producing mass concrete structures and piles
• Fixing ground anchors for sheet pile walls, concrete pile walls,
retaining walls tunnels etc
• Repairing a ground underneath a formation or cracks and
structural
• Defects on building masonry or pavement.
• Fixing the tendons in prestressed post tensioned concrete
• Filling the void between the lining and rock face in tunnel
works
APPLICATIONS

4. (a) Suspension grouts: These are multi-phase systems capable of
forming sub systems after being subjected to natural sieving
processes, with chemical properties which must be carefully
scrutinized so as to ensure that they do not militate against controlled
properties of setting and strength. Water in association with cement,
lime, soil, etc., constitute suspensions. Emulsion (asphalt or bitumen)
with water is a two-phase system which is also included under
suspension.
(b) Solution grouts: These are intimate one-phase system retaining
an originally designed chemical balance until completion of the
relevant reactions. Solutions in which the solute is present in the
colloidal state are known as colloidal solutions. Chemical grouts fall
into this category.
GROUTING MATERIAL TYPES

5. • Cement and water
• Cement, rock flour and water
• Cement, clay and water
• Cement clay, sand and water
• Asphalt
• Clay and water
• Chemicals
MATERIALS USED FOR GROUTING

6. Common admixtures used with cement grouts:
1. Calcium chloride ]
2. Sodium hydroxide ]-----------------for accelerating setting time
3. Sodium silicate ]
4. Gypsum ]
5. Lime sugar ]----------------------for retarding setting time.
6. Sodium tannate ]
7. Fine bentonite ]
8. Clay ]
9. Ground shale ]--------for reducing cost of grout and reduces
10. Rock flour ] strength of grout
ADMIXTURES

7. Grout is injected into the soil at low pressure and fills the voids
without significantly changing the soil’s structure and volume.
Variety of binders are used with this technique, the choice of which
is dictated mainly by the permeability of the soil.
When the coefficient of permeability is greater than 10-2
cm/sec,
water-cement mixes are used and for permeability as low as 10-5
cm/sec, the more expensive resin based grouts are used. Soils with K
values lower than 10-6
cm/sec are normally not groutable by
permeation.
PERMEATION

8. The basic concept is of injecting an highly viscous grout with
high internal friction, injected into a compactable soil, the grout
acts as a radial-hydraulic jack and physically displaces the soil
particles thus achieving controlled densification.
Advantages
1.Minimum disturbance to the structure and surrounding ground,
2.Minimum risk during construction.
3.Ground water not affected.
4.Supports all portions of structures.
COMPACTION PERMEATION

9. Disadvantages
•Grouting adjacent to unsupported slopes may be ineffective.
•Not suitable in decomposable materials.
•Danger of filling underground pipes with grout.
•Effectiveness questionable in saturated clays
COMPACTION PERMEATION

10. Thick slurries can not penetrate fine cracks and higher
injection pressures would cause fracturing of ground foundations.
Because of the higher water requirements of micro fine cement,
the slurry remains fluid enough to flow into and penetrate fine
sands and small cracks in rock.
These cements can treat finer grained sands not possible to
treat with Portland cement alone. They are also used to stabilize
waste plumes.
MICROFINE CEMENT

11. A key advantage of chemical grouting is the ability to introduce grout into
soil pores without any essential change in the original soil volume and structure,
thus changing the support capability of granular soils without disturbing them.
Another advantage is the ability to be less disruptive and enable tunneling to
proceed without over-excavation. A possible drawback of chemical grouting is
that only certain soil types are amenable. Another barrier to the use of chemical
grouting techniques in the recent is increasing concern regarding potential
pollution by chemical grouting in urban areas. Two trends have addressed this
issue:
1. Improvement of grouts through the development of new formulae that
enhance the penetrability of particulate suspensions and meet the strictest
specifications for environmental safety
2. Development of alternative techniques which by-pass the penetrability
restraints, such as jet grouting which allows the treatment of most types of soil,
independent of its grain size and permeability, using simple cement grouts
CHEMICAL GROUTING

12. COMPACTION PERMEATION

13. 1.Compensation (hydrofracture) grouting uses high-mobility
grout to split the ground and thereby create lifting or densification
under structures or other facilities.
2.The ground is deliberately split by injecting stable fluid
cement-based grouts at high pressures in order to increase total stress
by the wedging action of successive thin grout lenses, to fill
unconnected voids, and possibly to consolidate the soil locally under
injection.
3.This process is often undertaken as a reaction to movements
while tunnel excavation is in progress.
4.It is important to keep in mind that the effects of compensation
(hydrofracture) grouting are difficult to control and the potential
danger of damaging adjacent structures by the use of high pressure
may prove prohibitive
COMPENSATION GROUTING

14. 1. It is a technology in which high- pressure jets of cement grout
are discharged sideways into the borehole wall to
simultaneously excavate and then mix with the soil.
2. The outstanding feature of jet grouting is the ability to treat a
whole range of soils, from silty sands to cohesive deposits, by
means of simple cement grouts.
3. Jet grouting can be performed in soils with a wide range of
granulometries and permeabilites.
JET GROUTING

15. 1. the ability to use very small drilling tools (90mm diameter) to
create large elements (1.2m to 2.4m diameter) using pressure
and flow;
2. the ability to drill underneath obstacles and solidify zones
which are hard to access;
3. the use of technically sophisticated techniques such as high-
powered pumps and monitoring devices with continuous
measurement of all operational parameters.
ADVANTAGES

16. JET GROUTING

17. A grouting plant includes a mixer, an agitator, a pump, and
piping connected to grout holes. Two systems: single line type and
circulating type. In the circulation type, the unused grout is returned
to the agitator and in the single-line type the grout refused is wasted.
The basic items required for a grouting plant and their functions are:
(a) Measuring tank-to control the volume of grout injected.
(b) Mixer-to mix the grout ingredients
(c) Agitator-to keep the solid particles in suspension until pumped
(d) Pump-to draw the grout from the agitator to deliver to the
pumping line.
(e) Control fittings-to control the injection rate and pressure so that
the hole can be regularly blend with water and thin grout.
GROUTING PLANT AND EQUIPMENT

18. SCHEMATIC REPRESENTATION

19. PRECAUTIONS
The following are the precautions while mixing a grout:
• Water is placed first in the mixer.
• Mixer is run at the maximum speed before adding the cement.
• Grout is mixed in batches.
• Ingredients have to be measured in volume
• Enough water should be maintained to cover the rotor while it
is functioning.
• Mixer should not be allowed to run for more than a few
minutes between batches.
• Mixers should be cleaned thoroughly after the day’s work.

20. Holes for the injection of grout may be drilled with jack
hammers, wagon drills or diamond drills, depending on the
terrain, class of foundation material, and size and depth of holes.
Diamond drills usually give holes of uniform shape, while wagon
drills are satisfactory for holes up to about 10 meters depth.
DRILLING INJECTION HOLES

21. Preparations for washing or grouting seams, consists of
installing a section of pipe of about 35 to 50mm dia and 0.50 to
1.0 m long in the grout hole with the top and projecting out a
short distance for connection to an air line or a pump.
For grouting the seams with neat cement for consolidation
purposes it is desirable to deposit the cement in clean seams by
removing any clay or any other unwanted materials. For this
cleaning effective method is to force a mixture of air and water
through the seams.
For deciding the pressure for grouting operation, most
common practice is to use a pressure 0.2kg/cm2 for each meter
of depth of hole.
WASHING AND GROUTING THE SEAMS