SHRP-A-379 traducir

4.3.5 At the compIetion of the test, remove the test assembly from the shear test
device.
4.3.6 Disassemble the test assembly. Discard or retain the test specimen and clean
the end caps for reuse.
5. GUIDELINES
5.1 The following guidelines must be carefully followed before attempting to perform
any of the tests described in this practice.
5.1.1 Ensure that all load cells and LVDTs are accurately calibrated.
5.1.2 Ensure that the correct channels and gains are entered into the system software
before beginning any test.
5.1.3 Clearly define the test conditions and enter them into the test device software.
5.1.4 Allow sufficient time for the system to stabilize after the specimen is placed in
the apparatus and before the test begins. This time will vary depending on the test
temperature and the stiffness of the specimen. A typical stabilization time is 15 to 30
minutes.
5.1.5 Clearly identify the variables which are to be measured during the test.
5.1.6 Turn on the hydraulic system 1 hour before starting the test to allow sufficient
warm-up time.
5.1.7 Condition all specimens at their initial test temperature for 2 hours before
testing. For testing at 40°C or higher, the specimen should be placed in a 40°C (or
designated temperature) oven for a period of at least 2 hours but not more than 4 hours.
5.1.8 After the specimen is placed in the shear test device, apply a pre-load of 100 to
150 N before the specimen is clamped in place.
5.1.9 Perform a thorough check of the system for leakage before any test requiring
specimen confinement with air pressure.
5.1.10 Ensure that all measurement devices have reasonable sensitivities,
commensurate with the load intensity and specimen deformation expected during each test.
For example, the frequency sweep test requires a much more sensitive LVDT for horizontaI
deformation measurement than for vertical deformation.
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