STANDARDS:SPECIFICATIONS

BS8110 Pt :1997Clause 3.12.8.16.2

The only form of full strength Butt joint for a bar in Tension comprises a mechanical coupler satisfying the below criteria:

ACl 318-95 Clause 12.14.3.4

A full mechanical connection shall develop in tension or compression ,as required,atleast 125% of specified yield strength of steel bar.

IS16172:2014 lCS 77.140.15

The Indian standard for Reinforcement Couplers for mechanical splices of bars in concrete.

When a test is made of a representative gauge length assemblecomprising reinforcement of the size,gradeand profile to be used,and the couplers of a precise type to be used,the permanent elongation after loading to 0.6fy should not exceed 0.1mm.

The Tensile strength of the coupled bar should exceed

• 518.0 N/mm2 :for Grade Fe415

• 625.0 N/mm2 :for Grade Fe500

• 687.0 N/mm2 :for Grade Fe550.