ASTM A1034 | Metals | Mechanical Splice
ASTM A1034 is a testing standard that covers the testing of mechanical splices for reinforcing bars. The bar-splice assembly consists of two reinforcing bars connected with a mechanical splice and represents the mechanical splice used in practice. Results obtained from testing the bar-splice assembly can be used to determine the acceptability of the mechanical splice for use in reinforced concrete structural members under specific design criteria.
The various test methods described in this standard are applicable to any type of mechanical splice manufactured to join steel reinforcing bars of any grade, uncoated or coated. The standard covers tension, compression, cyclic load, high-cycle fatigue, and slip tests. It is also recommended to run each test in low temperatures to ascertain the behavior of the bar-splice assembly under temperatures at the critical zone. Finally, features of one or more of the tests can be combined to run combination tests.
Prior to conducting ASTM A1034, it is important to read the entire specification in the relevant ASTM publication.
ASTM A1034 | Metals | Mechanical Splice
Procedure A – Baseline Tension Test
- Measure and record the specimen dimensions necessary to determine the cross sectional area.
- Mark the gauge length with a center punch, scribe marks or draw with ink. The distance between the gauge marks after the specimen is broken is used to determine the percent elongation at break.
- Zero the testing machine without the specimen inserted in the grips. Install the specimen in the grips and attach at least two axial extensometers to the specimen. Please note that the extensometer needs to be removed prior to specimen failure. ADMET software stops test and prompts the removal of the extensometer once the total strain data has been satisfactorily obtained.
- Start loading the sample. The speed of testing is generally specified in one of three manners: a) rate of movement of the crosshead of the testing machine when not under load; b) the rate of stressing of the specimen; or c) the rate of separation of the crossheads under load.
- Run the test until specimen failure or fracture.
- Record the stress-strain behavior and the yield and tensile strength of the bar.
Procedure B – Monotonic Tension Test
- Follow the same instructions on Procedure A, above. Up to the yield point, apply load at a rate between 70 MPa/min (10 ksi/min) and 700 MPa/min (100 ksi/min).
- Run the test until specimen reaches the yield strength of the bar. Once the yield point is reached, remove the extensometers and continue test until specimen failure.
- Record the stress-strain behavior and elongation of the test specimen continuously.
Procedure C – Monotonic Compression Test
- Follow the same instructions as Procedure A, above, using a compression test set up and compression platens. Deflectometers for measuring compressive strain is not required for this test.
- Apply the load at a constant speed where the minimum strain rate is equal to 0.005/min in the elastic range.
- Run the test until compressive load reaches that specified.
Procedure D – Cyclic Load Test
- Follow the same instructions as Procedure B, above, until the strain specified has been reached.
- Reverse the crosshead loading direction once the specimen reaches the compressive loads specified. Apply the load at a minimum strain rate equal to 0.005/min in the elastic range. After reaching the yield, load the specimen at the strain rate specified.
- Apply the load in tension to the specified tensile strain and then in compression. Repeat this procedure until the specified number of cycles at this maximum tensile strain is completed.
- Repeat this procedure for each strain group increment until all of the tension-compression cycles for all strain group increments specified have been completed.
- Following the last cycle, apply tensile load to failure.
Procedure E – High Cycle Fatigue Test
- Follow the same instructions as Procedure B, above, until the upper tensile stress specified has been reached. Then, decrease the tensile force to the lower tensile or compressive force specified.
- Refer to the test standard to determine the frequency of tests.
- Repeat this procedure until the specified number of cycles has been reached.
- Following cycling loading, apply tensile load to failure.
Procedure F – Slip Test
- Apply tensile force not exceeding 4 MPa (600 psi) to the bar-splice assembly. Record the zero extensometer reading over the gauge length across the splice.
- Then, load the bar-splice assembly in tension to a predetermined load. Up to the yield point, apply load at a rate between 70 MPa/min (10 ksi/min) and 700 MPa/min (100 ksi/min).
- Unload the specimen at the same near zero load and measure and record the extensometer reading.
- Record the difference between the extensometer readings at near zero under load under step 1 and step 3 as the slip within the bar-splice assembly.
ASTM A1034 | Metals | Mechanical Splice
ASTM A1034 | Recommended Equipment |
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Testing System | For static testing only:
For static and dynamic testing: |
Fixturing | |
Accessories |
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