Testing Procedure
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Testing Procedure
From the Main menu you can choose among 3 different test modes
(or methods):
•
Longitudinal frequency (E)
•
Transverse frequency (E)
•
Torsional (G)
Longitudinal Frequency Mode
The Longitudinal Frequency mode is selected by placing the cursor
on the first line, and pressing ‘Enter’. For this mode the user can
input the desired value of the Modulus of Rigidity (G) that will be
used for the
Poisson’s Ratio calculations.
The user should input the required parameters below using the
arrow keys:
Specimen’s shape – Cylindrical or Prismatic
M: mass of the specimen (kg)
L: length of the specimen (m)
d: diameter of cylinder (m)
t, b: dimensions of cross section of prism (m), t being the driver (or
impact) direction in which it is driven (Note: It is important to
distinguish between t and b for transverse frequency).
G: assumed Modulus of Rigidity value in order to compute (
μ)
Usually, the user has to input the value of G in G Pa obtained in a
previously run Torsional test.
E: assumed Modulus of Elasticity value in order to compute
μ.
Usually, the user has to input the value of E in G Pa obtained in a
previously run Longitudinal or Flexural test.
The system provides the fundam
ental longitudinal frequency (n’)
from the FFT, frequency value of the maximum Amplitude on the
FFT, which is applied to a time domain signal obtained by slightly
tapping the cylinder with a small hardened steel ball.
