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INTRODUCTION
The Gilson HM-381 Standard Pneumatic Direct Shear
Machine is a tabletop unit that provides direct or di-
rect/residual shear values for evaluating the strength
and stability of soils. Manufactured in cooperation with
Karol-Warner, this device utilizes a pneumatic loading
piston for applying the vertical load to the sample. A
calibration chart is included for setting the high load or
the low load via the Fairchild Regulator while a built-in
digital readout displays the vertical load in psi.
This Direct Shear Unit has a strain rate of 0.0001 –
0.3 in/min (0.0025 – 7.62 mm/min) with a maximum
shear displacement of 0.8in (20.3mm) and the travel
speed is set with the thumbwheels on the left side of
the unit. The residual shear force is determined by a
load cell while real time load settings and peak load
are displayed on the digital readout. Consolidation and
shear displacement are measured with analog dial in-
dicators.
FEATURES
• Total shear capacity of 1,500lbf (6.67kN)
• Stepper motor controls strain rates to +/- 1% from
0.0001 – 0.3in/min (0.0025 – 7.62mm/min
• Teflon coated anodized aluminum water chamber
with drainage port included.
• Meets requirements for ASTM D3080 and
AASHTO T 236
REQUIRED ACCESSORIES (purchased separately)
• Direct shear boxes are sold separately and are
available in a wide range of inch and metric sizes
with round or square shapes. See all options at
www.globalgilson.com and in chart below.
– Direct Shear Boxes and Accessories
Direct Shear Boxes & Accessories
Description
Shear Box
Cutters
Extruders
Porous
Stones
Round Direct Shear Boxes
50mm (1.97in) Diameter
2.0in (50.8mm) Diameter
60mm (2.36in) Diameter
2.42in (61.4mm) Diameter
2.5in (63.5mm) Diameter
100mm (3.94in) Diameter
4in (101.6mm) Diameter
HMA-733M
HMA-733
HMA-734M
HMA-734
HMA-735
HMA-737
HMA-736
HMA-743M
HMA-743
HMA-744M
HMA-744
HMA-745
HMA-747
HMA-746
HMA-763M
HMA-763
HMA-764M
HMA-764
HMA-765
HMA-767
HMA-766
GSA-208
GSA-210
GSA-213
GSA-217
GSA-219
GSA-231
GSA-232
Square Direct Shear Boxes
50mm (1.97in) Square
2.0in (50.8mm) Square
60mm (2.36in) Square
2.42in (61.4mm) Square
2.5in (63.5mm) Square
100mm (3.94in) Square
4in (101.6mm) Square
HMA-733MS
HMA-733S
HMA-734MS
HMA-734SA
HMA-735S
HMA-737S
HMA-736S
HMA-743MS
HMA-743S
HMA-744MS
HMA-744SA
HMA-745S
HMA-747S
HMA-746S
HMA-763MS
HMA-763S
HMA-764MS
HMA-764SA
HMA-765S
HMA-767S
HMA-766S
GSA-208S
GSA-210S
GSA-213S
GSA-217S
GSA-219S
GSA-231S
GSA-232S
• A constant supply of compressed air at 90psi (6.2
bar) is required for use.
UNPACKING & SETUP
• Inspect your HM-381 for damage, remove from the
pallet.
• Place Direct Shear Machine on a sturdy, level sur-
face, such as a bench top or HMA-95 Pneumatic
Shear Machine Rolling Cart.
• Review the Connections section and install neces-
sary components.
HM-381 & HM-381F Standard Pneumatic Direct
Shear Machine
OPERATING MANUAL
Rev: 05/2020
PHONE: 800-444-1508
P.O. Box 200, Lewis Center, Ohio 43035-0200
740-548-7298
E-mail: [email protected] Product Web Page:
FAX: 800-255-5314
740-548-5314
HM-381
