The filling of voids in an inert material (soil , rock , deteriorated concrete
or masonry , etc .) with a liquid grout which subsequently solidifies renders
the material improvious and / or improves its strength
Strictly speaking , this classic technique used in both new construction and
repairs should be called impregniation grouting , as opposed to more recent
innovations with more specific objectives , such as "jet grouting" and "compaction
grouting" .
PROCESS
The grout is injected into the ground through boreholes , fitted out to suit
the type of material involved . An uncased borehole is suitable in rock , as
where loose soils may require the use of a sleeved grout pipe ("tube à manchettes")
.
Schematically , a grouting job involves three stages :
- Drill and fit out boreholes
- Mix grout
- Inject grout
HISTORICAL DEVELOPMENT
Grouting has been an established engineering technique for a relatively long
time - about 40 years in soils and distinctly longer in rock - and has undergone
continual development .
Key items in improving the technique have been :
- The variety of rotary , percussion rotary and vibration drilling machines
for increased efficiency in most types of ground .
- Modular design of grout mixing plant which can be quickly moved around the
site and rapidly assembled.
- The appearance of almost fully automatic mixing plant .
- The introduction of flexible hoses instead of grout pipes , fitted with inflatable
packers .
- The very wide range of grout mixes now available , which has continually pushed
back the limits of the technique .
RECENT PROGRESS
As leading soil improvement specialists , SOLETANCHE - BACHY have a commitment
to innovation and development .
Two crucial areas of progress have been :
- New grouts with the focus on pollution control , production of durable mineral
products and improved penetration
watertightness and strength performance .
- The introduction of electronics at all stages of design office and site worksite
investigation , design , jobsite grouting and quality control offering scientific
rigour and clarity .
(see ENPASOL - SINNUS - EPICEA)
Modern grouting now has a new image . It has become an indispensable high -
tech tool in major engineering construction .