Shortcreting
has proved to be the best method for construction of curved surfaces. Domes are
now much easier to construct with the advent of shotcrete technology. Tunnel linings
are also becoming easy with this technology. Not only are these but there a wide
range of applications where this technology has been a leading one. This
technical paper includes the concept of shotcrete and how it differs from conventional
concrete. It also enumerates the different types of process involved in shotcreting
i.e. dry mix process and wet mix process. Advantages of shotcrete and its applications
in various fields like tunneling, canals, buildings etc. are specified in
detail. This paper presents an overview of shotcreting technology along with
its applications.
DEFINITION OF SHOTCRETE:-
Shotcrete
is a mortar or high performance concrete conveyed through a hose and pneumatically
projected at high velocity onto a backing surface. It is the force of this spraying
action that leads to compaction of the concrete or mortar which then forms layers
of concrete to the required thickness. Shotcreting has been an acceptable way
of placing cementitious material in a variety of applications.
Usually
patented polypropylene fibers are included in the shotcrete which increases the
cohesive nature of the shotcrete through mechanically binding the cementitious
materials together. This mechanism reduces the rebound waste that occurs through
the shotcreting process and these fibers also resist plastic shrinkage and
cracking through their ability to enhance the early stage tensile strength of
concrete.
Shotcrete
also gives better surface finishes and reduces surface tearing on non- linear
sections. Cementitious material containing the poly propylene fibers resist
cycles of freezing and thawing and also reduces the chances of water and
chemical penetrations.
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