Indented PC wire

In the application of pre-tensioned concrete, the pre-stressed steel wire is
initially tensioned to approximately 70 to 80% of the minimum specified
breaking load of the steel wire before the concrete is cast. Once the concrete
sets to a certain degree, the pre-tensioned steel wire is released, and this
induces compressive stress in the concrete. This compressive stress helps
offset the tensile stress caused by the loads acting on the concrete member.
For effective pre-tensioning, it is crucial to establish a strong bond between
the steel wire/bar and the concrete. This bond allows the desired compressive
force to be efficiently transferred from the steel wire to the concrete.
One method to improve the bond strength and achieve a consistently low
transmission length is by introducing regular indentations of a specified shape
on the surface of the steel wire/bar. These indentations can be slotted in
opposite or 120-degree or 90-degree planes.
To create indented steel wire or rod, a process known in the industry is to
perform intermittent indentation on the wire's surface using appropriate
indenting rolls. Typically, this indentation process takes place on a wire-
drawing machine, where the wire is pulled through the indenting rolls to
achieve the desired pattern.

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