ISO 15835–1:2018 - Standard for reinforcement Couplers

ISO 15835–1:2018 - Standard - Steel for the reinforcement of concrete – Reinforcement couplers for mechanical splices of bars

ISO 15835 & NF 350-20

 

ISO 15835 & NF 350-20
Type of Test Required	Why ! (Purpose of the test)	What is the Criteria ?
Static tensile strength test	Tensile strength of the Rebar joint (Rebar to Coupler Splice) joint	>ReH(Rm/ReH) ReH - Refers to beginning of yield point elongation Rm - Tensile Strength
Slip Test	Used to make sure that the plastic movement (slip) between the reinforcement bars with in the Mechanical Splice, when Loaded in tension	<=0.10 mm after applying A minimal force of 0.7ReH (=bar’s nominal yield stress) is used to measure slip at the splice ReH - Refers to beginning of yield point elongation
Uniform Cyclic Load Test (Seismic Elastic)	Used to make sure how a mechanical splice performs when subjected to alternating tension and compression loads for a given number of cycles.   Each cycle may exceed the specified yield strain of the reinforcement bar and is intended to stimulate an earthquake loading.	20 Cycles of stress variation from 50% to 90% of fy
Stepped Strain Cyclic Load Test (Seismic Plastic)   Stage 2,3 & 4		4 Cycles of stress variation from (-50%fy to 2εy)   4 Cycles of stress variation from (-50%fy to 5εy)
Fatigue Loading
High cycle fatigue test	Similar to a cyclic load test, but with the test load staying below the yield strength of the bar. The test is conducted until failure or a specified number of cycles are reached.   The test is meant to stimulate a mechanical splice in a bridge or other structure subjected to frequent elastic load cycles.   High cycle Fatigue is the term used to designate the situation when more than 1,000 to 10,000 cycles are need before final rupture.   In this case average stresses are usually below the yield strength of the material, and most of the time is spent to initiate a crack.   High cycle fatigue is a type of fatigue caused by small elastic strains under a high number of Load cycle before failure occurs   The stress comes from a combination of mean and alternating stresses. The mean stress is caused by the residual stress, the assembly load, or the strongly non uniform temperature distribution.	2,000,000 (2 million) cycles.     0.6fy where fy=60MPa
Maximum % Elongation		0.7 x Agt  or   3% if Agt is not specified. Agt is % elongation of parent rebar at maximum tensile force.