This presentation is related about soil improvement techniques. It includes the basic definitions and types of grouting.

1. PRESENTED BY:-
SHOAIB BASHIR WANI
18-CE-08
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2.  Introduction
 History & Development of Grouting
 Grout & its types
 Desirable Characteristics of Grout
 Grouting Methods
I. Permeation Grouting
II. Displacement-Compaction Grouting
III. Displacement-Soil Fracture Grouting
IV. Jet or Replacement –Displacement Grouting
V. Rock Fissure Grouting
VI. Tube-a-Manchettes(TAM) Grouting
• Conclusion
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3. Injection of slurry or a liquid solution into a soil or
rock formation is termed as grouting. The injected
material is referred to as the grout. The process of
grouting was developed primarily as a technique
for making vertical seepage barriers beneath dams
and hydraulic structures by injecting cement slurry
into the void space of river bed material.
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4.  Its traceable record can be as early as in the beginning of 1800s.
 In 1802, the idea of improving the bearing capacity under a
sluice by the injection of self-hardening cementitious slurry was
first introduced.
 In 1893, the first systematic grouting of rock in the USA as
performed at the New Croton Dam, in New York.
 In 1960s, jet grouting technique was developed.
 In 1977, first application of compaction grouting for controlling
ground movement during construction of the Bolton Hill Tunnel.
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5.  Grout is a construction material used to embed rebars in masonry
walls, connect sections of pre-cast concrete, fill voids, and seal joints
(like those between tiles).
 Grout is generally composed of a mixture of water, cement, sand,
often color tint, and sometimes fine gravel.
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6. Suspension :- Suspensions consist of small-sized
particles dispersed in a liquid medium. These include
cement grouts, that is, slurry of cement in water; soil-
cement grouts consisting of slurry of soil and cement in
water; and Bentonite grouts comprising slurry of
Bentonite in water.
 Emulsion :- Emulsions consist of colloidal droplets of
liquid dispersed in a liquid medium; bituminous emulsion
fall in this category.
Solutions:- Solutions are liquid homogenous
molecular mixtures of two or more substances; chemical
grouts such as sodium silicate solutions and acrylic
resins are examples of solutions
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7. Properties of a grout are described in terms of five parameters:-
1. Groutability:- Expresses the ability of the grout to reach the
desired location in the soil, mass. To be able to do so the grout
should possess sufficiently high fluidity and the suspended
particles, if any, must be of a size that enables them to enter
the void spaces in the soil mass.
Groutability Ratio = D15 of soil / D85 of grout > 25
2. Stability:- Is the capacity of the grout to remain in a fluid state
and not segregate into its separate components. We need the
grout to be stable until it has reached its destination. Stability
of clay-cement grout is usually more than that of a cement
grout.
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8. 3. Setting Time:- Is the time it takes before the grout sets into a cemented
mass or gel. Early setting can cause difficulty in grout reaching its
destination and late setting can result in the grout being washed away if
seepage is occurring through the soil. Additives are used to retard or
accelerate the setting time as required.
4. Permanence:- Indicates the resistance the grout possess against being
displaced from the soil voids with time. Cement grouts have greater
permanence than Bentonite grouts which can get washed away with time
by seepage of water through the grouted zone.
5. Toxicity:- Is the capacity of the grout to contaminate the ground water
coming in contact with it and of adversely affecting the health of workers
handling and injecting the grout into the soil.
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9. 1. Permeation Grouting
2. Displacement-Compaction Grouting
3. Displacement-Soil Fracture Grouting
4. Jet or Replacement-Displacement Grouting
5. Rock-Fissure grouting
6. Tube-a-Manchettes(TAM) Grouting
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10. 1. Permeation Grouting:- Permeation Grouting is defined as a
means of impregnating the voids within a soil or rock mass and
thereby displacing water and air from the voids and replacing it
with grout, without displacing the soil particles or widening the
existing fissures in the rock. It includes:-
• Injection of thin grouts into the soil.
• Once the soil cures, becomes a solid mass.
• Done usually using chemical grouts.
• Used for creating groundwater barriers or
preparing ground before tunneling.
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11. Application of Permeation Grouting:-
Permeation grouting is widely used for making vertical
seepage barriers beneath hydraulic structures. It is also
used for stabilization of soil around tunnels and shafts.
Other uses include stoppage of seepage through joints of
underground structures such as tunnel lining, basement
wall etc.
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12. (a) Grout curtain beneath dam
(b) Stabilization of crown of tunnel with chemical grout.
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13. Conceptual Diagram of Soil Solidification by
Permeation Grouting.
Grouting Pressure:- To enable rapid permeation of grout slurry into
the void space, a high injecting, that is, grouting pressure is desirable. It
must not, however, cause the soil mass to displace or to fracture. Hence
the grout pressure has to be limited to 25% of the effective overburden
pressure at the depth of grouting .
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14. At point A, the state of vertical effective stress is as follows:
Vertical effective stress =ơ/
v = Ɣt h(major principal stress),
and for soils in the ‘at rest’ condition,
Horizontal effective stress =ơ/
h =KOƔt h(minor principal stress)
=
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Grouting Plant for permeation grouting
using cement grout.

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2. Displacement-Compaction Grouting:- Compaction grouting is the
injection of a thick, low mobility grout that remains in a homogeneous
mass without entering soil pores. As the grout mass expands, the
surrounding soil is displaced and densified. A conceptual drawing of
compaction grouting is shown below:-
—When low-slump compaction grout is injected into granular
soils, grout bulbs are formed that displace and densify the
surrounding loose soils.
—Used to repair structures that have excessive settlement

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Application of Displacement-Compaction Grouting:-
Situations where displacement-compaction grouting is most applicable

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3. Displacement-Soil Fracture Grouting:- Soil fracture grouting
technique is a displacement grouting technique in which a learn
slurry of cement, soil and water is injected into the soil at high
pressure to fracture the soil and form root-like or thin lens shaped
zones of grout material in the soil mass. The grout material
spreads all around the grout hole causing densification of the soil
mass and an increase in its macroscopic strength.
Restoration of verticality of a tilted building.
Displacement-Soil Fracture
Grouting

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4. Jet or Replacement-Displacement Grouting:-
In this technique, a special grout
pipe called the monitor having high-speed jets of water or grout is
used to erode and excavate the soil. Thereafter, as the monitor is
withdrawn, strong, impervious columns are produced by mixing
grout with the remaining soil.
Developed in Japan–Uses a special pipe with horizontal jets that
inject grout into the ground at high pressures.

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The sequence followed in jet grouting

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Application of Jet-Grouting:-
Grouted Columns:-
Jet grouted columns can be formed in almost all types of soil
ranging from sandy gravels to clays. Sands are best suited for
treatment yielding the largest diameter of columns. Presence of
inter particle attractive forces reduces the erosive efficiency of the
jets. Hence diameter of grouted columns are progressively smaller
in sandy silts, silts, clayey silts and clay. Gravels do not respond
well to jet grouting both because of loss of water or grout through
its voids and the difficulty in removing gravel particles.

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Applications of jet grouting
5. Rock Fissure Grouting:-
Rock fissure grouting is the use of a hole drilled through the fissures
and joints of a rock mass to allow grout to be injected at close
centers vertically and re-injecting, if necessary.
 Grouting Mechanism
There is only one grouting mechanism for rock grouting. The
following schematic diagrams show how the mechanism for grouting
in rock is. The grout is injected under pressure through the grout
hole drilled into the rock mass to be treated.

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Grouting in Progress Grouting Completed

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Application of Rock-Fissure Grouting:-
1. Sealing rock mass underneath and at ends of dams to prevent
seepage or leaking of the reservoirs.
2. Sealing rock mass above and underneath a rock tunnel to prevent
water seepage into the excavated tunnel.
3. Cementing fractured rock mass. Its main application is in the field of
water stopping, especially in tunnel excavation project.

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6. Tube-a-Manchettes(TAM) Grouting:-
Tube-à-Manchette (TAM) grouting is the use of sleeved
perforated pipes in grout holes, soils or completely decomposed
rock to allow grout to be injected at close centers vertically, and
re-injected, if necessary.
Grouting Mechanism:-
It is a grouting technique for grouting in soil formation only, with
partial or complete displacement of in-filling ground water.
Schematic Diagram of the
Impregnation Mechanism for
TAM Grouting

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Applications of Tube-a-Manchettes(TAM) Grouting:-
1. Sealing soil mass above and underneath a tunnel excavated in soil
under compressed air condition.
2. Sealing “windows” in cofferdams.
3. Consolidation of loose soil mass (cohesion less granular sand).
4. Sealing underlying soil of dams

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CONCLUSION
Grouting is a popular ground treatment technique, but not
so many engineers are familiar with it. And they often have
misconception about grouting. The project is to clarify on
one hand the basics of grouting, and then on the other
hand try to provide a full coverage of all types of grouting
mechanisms in practice. For each grouting mechanism, a
brief discussion is given to its design considerations,
construction and application. Finally, finite element
method is used to analyze and model grouting to confirm
the extent of grouting in terms of treatment zone and
degree of improvement of ground properties required.

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