4.1 Comparison of Overlapping & Welding of Reinforcement Bars
The maximum length of reinforcement steel bar available in market is approximatey
12 meters. Reinforcement bars are joined together with different mechanism so
as to transfer the load of structural element from one bar to other. This joint of
bars is termed as “splicing of reinforcement bars”. Splicing of reinforcement bars
can be done either by overlapping or by Welding procedures.
This technical note presents the comparison of splicing methods by overlapping
and welding of the reinforcement bars and their cost implications and effectiveness.
4.2 Overlapping of Reinforcement Bars
IS 456: 2000 recommends the minimum length of overlapping based on bond
strength between concrete & reinforcement bars. This length is termed as
“devel opment length” of the reinforcement bars, which depends on the grade of
concrete, diameter of the bar & ultimate strength of the material of the reinforcement
bar.
Table -1 provides the minimum requirement of the development length factor for
Fe500 grade of steel based on different grade of concrete and diameter of bars.