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.
- 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
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).
RockSchmidt Type N, including battery charger with USB cable, DVD with PC software, carrying strap, grinding stone, documentation and carrying bag
||(N) 2.207 Nm, (L) 0.735 Nm
||75 mm (2.95")
||25 mm (0.98"
|Dimensions of housing
||55 x 55 x 250 mm (2.16" x 2.16" x 9.84")
|No. of impacts in a series
|Memory capacity dependent on length of test series
||400 series with 10 values per series
||200 series with 20 values per series
||17 x 71 pixels; graphic
||>5000 impacts between charges
||USB type B (5V, 100 mA)
||0 to 50°C
||-10 to 70°C