The features of the hammer make it ideal for rock testing applications:

• Impact Angle Independence: The rebound value is independent of the impact direction.
• Optimised for Field Work: Tighter sealing against dirt and dust intrusion for longer life. Significantly lighter and more ergonomic than the classic Schmidt hammer. A large number of readings can be saved and downloaded later to a PC.
• Preset Statistics: Statistics methods recommended by ISRM and ASTM are implemented into the hammer for automatic calculation of the rebound number. The option is also there to define a user specific statistics method.
• Unconfined Compressive Strength: ISRM recommends a correlation between UCS and the rebound value based on the formula
• UCS = aebR (where R is the rebound value). A correlation in this format may be defined in the PC software and downloaded onto the RockSchmidt.
• E-Modulus: ISRM recommends a correlation between elastic modulus and the rebound value based on the formula Et = cedR (where R is the rebound value). A correlation in this format may be defined in the PC software and downloaded onto the RockSchmidt.
• Weathering Grade: Impacting on the same location twice can be used to correlate to weathering grade. The ISRM recommended method has been included in the device.

Applications:

• Geomorphological applications which investigate the bulk hardness properties of a rock outcrop
• Prediction of weathering grades
• Relative dating of landforms such as moraines and rock glaciers
• Correlation to Unconfined (or Uniaxial) Compressive Strength (UCS)
• Correlation to Young’s Modulus
• Prediction of penetration rates for tunnel boring machines and rotary drum cutters
• Testing on cores ≥ 84 mm Ø ≥ 54.7mm Ø
• Testing on rectangular blocks > 100mm thick

Type N:

Standard impact energy, 2.207 Nm.
Recommended for field work.
For core testing ISRM recommends that cores should be at least moderate strength (> 80 MPa) and at least T2 size (≥ 84 mm).

Supplied as:

RockSchmidt Type N, including battery charger with USB cable, DVD with PC software, carrying strap, grinding stone, documentation and carrying bag

Specification

Technical Data
Impact energy	(N) 2.207 Nm, (L) 0.735 Nm
Spring extension	75 mm (2.95")
Plunger radius	25 mm (0.98"
Dimensions of housing	55 x 55 x 250 mm (2.16" x 2.16" x 9.84")
Weight	570 g
Memory Data
No. of impacts in a series	Maximum 99
Memory capacity dependent on length of test series
Example	400 series with 10 values per series
Example	200 series with 20 values per series
Electrical data
Display	17 x 71 pixels; graphic
Battery lifetime	>5000 impacts between charges
Charger connection	USB type B (5V, 100 mA)
Environmental conditions
Operating temperature	0 to 50°C
Storage temperature	-10 to 70°C