Humboldt H-4212MH User manual

The Humboldt H-4212MH Pocket Shear Vane Tester comes with 3
vanes and an L-wrench to attach them to the unit. The small vane is
pre-attached to the unit and the standard and large vanes are attached
by sliding them over the small vane, aligning the set screw with the
indent on the small vane and securing them with the set screw.
To Use:
1) Mount the desired vane to the unit and make sure it is secure.
2) Align the “0” on the inner dial on top of the unit with the mark
on the outer ring using a counter-clockwise rotation while holding
the outer ring.
3) The test surface should be at least two inches in diameter and
relatively flat.
HUMBOLDT
1.800.544.7220 • www.humboldtmfg.com • 708.456.6300
Testing Equipment for Construction Materials

4) Press the unit into the soil sample until the blades are covered.
5) While maintaining a constant pressure, rotate the outer ring of the
unit. Turn the outer ring until failure occurs. (The speed of rotation
should be a speed that accomplishes failure within 5 to 10 seconds.)
6) Release the outer ring, slowly, once failure has ocurred. The mark on
the outer ring will remain in place indicating the shear value at failure.
7) Multiply readings by 0.2 when using large vane and 2.5 when using
small vane.
Vane Stress Range Usage
Standard 0 to 1 kg/cm2
Fully saturated cohesive soils
with undrained strength inde-
pendent of normal pressure
Large 0.2 kg/cm2Remolded samples
Small 2.5 kg/cm2Stiffer clays
www.humboldtmfg.com • 1.800.544.7220