Product Manual

3
Hardware
System Description
Dr. Baden Clegg developed the Clegg Impact Soil Tester while working for the Department
of Civil Engineering at the University of Western Australia in the 1970’s. The Clegg Hammer
is an easy-to-use device consisting of two basic components: a flat ended cylindrical mass
(the hammer) and a guide tube. When the hammer strikes the soil surface, a precision
accelerometer mounted on the hammer feeds its output to a Control Unit, which sends a
digital readout to a handheld tablet. A drop or sequence of drops of the hammer
constitutes one test called a Clegg Impact Test (CIT).
The Clegg offers a rapid, simple, and relatively inexpensive assessment of the strength and
stiffness properties of a variety of soils, aggregates, and synthetic materials. The impact
test result reflects and responds to characteristics that influence strength. Such influences
include material type, grading, layer thickness, density, moisture condition, and possibly
the condition of the underlying layer. With all things being equal regarding material type and layer thickness and the
nature of the support base, the primary influences are the density and/or moisture condition of the material. The CIT may
be used to observe changes in strength/stiffness for a material with the changes in compactive effort, density, and
moisture content.
Device Parts
UNIT
• Hammer
• Guide Tube
• Control Unit
• BNC coaxial cable
• 12x12 inch foam Calibration Pad
• Locking pin to attach hammer to guide tube
• Handle and Hammer Release Spring Plunger with lockout
• Charger
• Tablet with Clegg Control App (available in the Google Play store)
ACCESSORIES
• Hard Case (sold separately)
Specifications
Model
Maximum Gravities (g)
Maximum CIT’s
2.25 kg Unit
150
15
• Battery Life: 12 Hours
• 3.7V/1.75Ah Lithium Ion Battery
• Complete Charge in 3 hours
• Results displayed/stored on tablet-based app