Geotechnical News • June 2017
25
THE GROUT LINE
Paolo Gazzarrini
Overture
47th episode of the Grout Line and for
this issue a European experience with
the use of Multiple Port Sleeved Pipes
(or TAM) in soil grouting. The authors
Ing. Andrea Pettinaroli
, Dr. Mario Rug-
giero
and Ing.
Gabriele Balconi
)
prepared this article about a successful
compensation grouting project carried
out in Warsaw, Poland.
A case history of compensation grouting with the
TAM application in an urban area in Warsaw, Poland
Andrea Pettinaroli, Mario Ruggiero, Gabriele Balconi
Grouting is a technique used for
modifying the behaviour of a mass of
soil or rock by injecting cementitious
or chemical mixes. Different processes
of execution may lead to different
results, and the choice is a function
of the objective of the treatment and
of the type of ground. More than fifty
years ago, the introduction of sleeved
pipes also known as TAM (Tube A
Manchette) brought a lot of advan-
tages to this technology; it allowed for
widening of the use of the grouting,
leading in many cases to more easily
reach the purpose and to savings in
time and cost. The use of non- metal-
lic pipes is nowadays highly diffused
because the variety of pipe materials
available, such as plastics and com-
posites, allows for optimization of the
costs of the tubes as a function of the
kind and importance of the work. The
TAM pipe technology is used both in
soil and rock.
The TAM pipe is a tube, normally
made of plastic, perforated at a regular
distance, with rubber sleeves mounted
on the holes to prevent the flow-back
of the mixtures inside the pipe. For
standard applications the pipe’s outer
diameter ranges usually from one to
two inches (Fig.1).
After identifying the area to be treated
and method of treatment required it is
necessary to proceed with the realiza-
tion of the pre-drilled and cased holes
where the pipe will be inserted, by a
conventional drilling rig. The sleeved
pipe is installed and sealed into the
hole by means of a suitable plastic
cement mixture (sheath) in granular
soils, or alternatively through the use
of geotextile bags in rocky soil acting
as packers. The sealing prevents the
injection mixture from raising up
along the borehole and penetrating
in the area of influence of the single
sleeve.
Once the annular space around the
pipe is sealed, the pressure injection
is carried out through a single valve
with a double packer (mechanical or
Figure 1. DURVINIL grouting tubes with raised sleeves (left) and with flush
sleeves (right).
