Humboldt HS-4210 Digital Static Cone Penetrometer - Manual (Page 6)

6
Correlations
(continued)
Uniform Clay and Silty Clays
Q
c
= 5 Q
u
Q
c
= 10 C
Clayey Silts
Q
c
= (10-20) Q
u
Q
c
= (20-40) C
CBR = Value (%)
Q
c
= (2.5-3.3) CBR
Maintenance
Testing with the Humboldt DSCP causes wear on the metal parts that make up
the device. In order to ensure maximum service life, periodic inspections of the
Humboldt DSCP for fatigue or damage are recommended. Any parts found
to be fatigued or damaged should be repaired by the manufacturer, or replaced
with Humboldt DSCP parts. The Humboldt DSCP should be kept clean and
all soil removed from the Drive Rod and Drive Cone Assembly after each use.
Lubrication of the inner rod is recommended using a few drops of machine oil.
The outer rod should be kept clean and lubricated with oil to aid in penetration
and cleanup as well as reducing corrosion.
Calibration available as required.