Volume 22, Issue 2 (March 1994)
Testing Techniques for Measurement of Bulk Modulus
The objective of this study was to examine prospective tests for determining the bulk modulus of elastomers used in the construction of elastomeric bearings. Because elastomeric materials are nearly incompressible, relatively slight volume changes are experienced during isotropic compression, sizably governing the accuracy of test measurements. For this reason major topics of interest are equipment calibration, test repeatability, and error accountability.
Test methods explored included use of a deformation jacket, a fluid displacement volume change measurement device, and load ram displacement for measurement of volume change. For verification of test methods specimens of Adeprene were tested.
Results from all test methods were found to be suitably, but not equally, repeatable. Considering ease of operation, and acceptability of errors, the load ram method is found to be superior compared to other methods investigated.