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• Equipment required:

  • Special Alignment Jig as shown in the figure below.

• Apparatus will be a compression test fixture

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• Get ready because this is a HEFTYYY procedure 

• General instructions:

  Condition specimens

  before/after strain gaging as required. Condition travelers if they will be used

• Apply strain gages/extensometers to both faces of the specimen

• The loading rate should produce a failure within 1 to 10 min. 

  • Strain-Controlled Tests, standard strain rate of 0.01 min/1 ?? I think the unit may be wrong here. I think it's supposed to be mm/min??

  • Constant Head-Speed Tests, A standard crosshead displacement of 1.5mm.min. 

• Monitor test temp by placing a thermocouple within 25mm of the specimen gauge section. You can also tape the thermocouple(s) to the test specimen and travelers. 

• Fixture Installation:

  • Place the lower wedge housing block on the lower platen, then attack the upper wedge housing block to the upper crosshead/insert it into the upper wedge housing holding fixture, centered over the lower wedge housing block. 

  • Move a crosshead to close the distance between the 2 housing blocks while guiding the bearing guide rods into the mating bearing of the companion housing block. The lower housing block can be fitted with guide rods long enough to allow the rods to remain in the bearings while the wedges or specimen assembly is loading into and out of the housing blocks. 

• Specimen Insertion:Monitor test temperature using thermocouples.

• If needed, move the testing machine crosshead to open the distance between the 2 housing blocks so both the upper and lower wedge rip assemblies may be accessed

  . 

• I’m so sorry but idk how to summarize the following thing :(

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• If the specimen will be aligned with the wedge grips in the fixture housing block, the lower jaws should be raised so that grip-faces open to allow specimen insertion.If we need to, free the upper wedge grips so they are in the fully open position. Moving the crosshead, close the distance between the housing blocks and guide the upper end of the specimen into the opening between the upper wedge grips. 

• Close the upper grips manually to check the specimens vertical displacement. Do it with the lower grips as well. The upper grips should be in full contact with the wedge when closed. Repeat if we need to. 

• Keep the grips closed and slowly close the distance between the housing blocks by moving the crosshead, watch the force indicator at this time. Stop the crosshead when the specimen begins to take a compressive force. 

• Transducer Installation:

  If the strain-transducer(s) other than strain gages will be used, attach them to the specimen at the mid-span, mid-width location

  Attach strain transducers if they will be used. Then, attach the strain recording instrumentation to the strain gages or other transducers on the specimen. Then, remove any remaining preload and zero the transducer(s).

• Loading:

  Apply the force to the fixture at the specified rate until failure while recording data.

• https://www.youtube.com/watch?v=qfHoq9w3glE I really like this video Tommy found and I believe it should give a really good idea of the test. 

This video is a good example of this test being carried out.

• Failure modes:

  • Record them by giving a code as shown below:

• There are a few unacceptable failure modes including end-crushing and euler buckling. 

*remember all these formulas will be in the astm document for finding the above values*