Rock Testing
INTRODUCTION
According to the “Committee on Rock Mechanics,
National Academy of Sciences”, rock mechanics is
a theoretical and applied science concerning the
physical behaviour of rocks subjected to stress
conditions of different origin. In general terms,
rock mechanics involves the study of underground
works such as tunnels, and surface construction
such as open quarries or dam foundations.
When a rock sample is subjected to defined
stress conditions in the laboratory, the stressstrain diagram can show behaviours of non
linearity also for very small strains, hysteresis,
anisotropy, fluage conditions, etc. All these phenomena can be mathematically described.
Contents
45
Rock mechanics
Rock sampling and sample preparation . . . . . . . . . . . . . . . . .
Strength and deformability tests . . . . . . . . . . . . . . . . . . . . . .
Automatic tests systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elastic modulus and strength characteristics
of rock specimens in uniaxial and triaxial conditions . . . . .
Hoek cells for triaxial tests . . . . . . . . . . . . . . . . . . . . . . . . . . .
Semi-automatic test systems . . . . . . . . . . . . . . . . . . . . . . . . .
Classification tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Splitting tensile test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Slake durability index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Permeability of rock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Behaviour of joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Measurement of shear strength . . . . . . . . . . . . . . . . . . . . . . .
Roughness measurement. Profilometers . . . . . . . . . . . . . . . .
Tilt test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strength index (point load) . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rock classification hammer . . . . . . . . . . . . . . . . . . . . . . . . . .
Testing equipment for the construction industry
168
171
172
173
175
178
180
180
180
181
182
183
183
183
184
184
167
45
ROCK TESTING
Rock sampling/ Sample preparation . . . . . . . . . . . . . . . . Rock picks/ Core Trimmer
 Rock picks
 Core trimmer and cut-off machine
Used for preliminary rock
identification.
M 45-D0536
Laboratory core trimmer and
cut-off machine, complete with
water inlet. 230 V, 50 Hz, 1 ph.
M 45-D1710
Rock pick pointed tip
Fully polished, leather grip.
A
M 45-D0536/Z
Same as above but 110 V, 60 Hz, 1 ph.
Weight approx.: 650 g
M 45-D1711
Rock pick chisel edge
Fully polished, nylon vinyl grip.
A
M 45-D0536/Y
Same as above but 220 V, 60 Hz, 1 ph.
q STANDARD
ASTM D4543
Weight approx.: 550 g
General description and specifications
M 45-D0529
Mohs hardness scale set
Used to obtain rock samples perfectly
machined (cubes, prisms, etc.) from irregular rock or core pieces. It is supplied
complete with a proper vice to hold irregular pieces firmly in place up to 70x140
mm approx. Another “V” vice is used to cut
cores to a maximum size 75 mm dia. x 140
mm height. Longer cores can be obtained
by turning the samples upside down in the
vice. It is supplied complete with cooling
water inlet. Blade cup wheel and water
pump must be ordered separately.
45-D1710, 45-D1711
Power: 1100 W
Speed of the blade: 3000 r.p.m.
B Dimensions: 730x1050x590 mm
A Weight approx.: 100 kg
Accessories for 45-D0536
core trimmer and cut-off machine
s45-D0536/1
Cooling recirculating pump complete
with reservoir. 230 V, 50 Hz, 1 ph.
s45-D0536/1Z
Same as above but 110 V, 60 Hz, 1 ph.
s45-D0536/1Y
Same as above but 220 V, 60 Hz, 1 ph.
s45-D0536/2
Diamond cutting blade. 230 mm dia.
x 2.5 mm thickness. Maximum cutting
area 110x70 mm
s45-D0536/3
Double-faced diamond cup wheel. 205
mm dia. x 16 mm thickness. Used for
finishing sample ends parallel and at
right angles to the axis
s45-D0536/4
Clamping device for irregular pieces
max. dim. 57x104x102 mm (length) and
core from 15 to 60 mm dia.
45-D0529
Detail of 45-D0536 with double-faced cup
wheel 45-D0536/3 during surface grinding of
cylindrical specimens ends
- Usable for both
trimming and surface grinding
- Usable to obtain
cube specimens from
irregular pieces
- Transparent protection cover conforming to CE directive
Detail of 45-D0536 with cutting blade
45-D0536/2 during operation
45-D0536 with 45-D0536/4
168
Testing equipment for the construction industry
45-D0536/3,
D0536/2
ROCK TESTING
. . . . . . . . . . . . . . . . Rock sampling/ Sample preparation
45
Cutting saws/ Coring machines
Models of core drill bits
 Cutting saws
 Coring machines and bits
M 45-C0210/C
Rock and masonry saw.
380 V, 50 Hz, 3 ph.
M 45-C0330
Laboratory coring machine,
2-speed, complete with water inlet.
230 V, 50-60 Hz, 1 ph.
M 45-C0210/CZ
Same as above but 220 V, 60 Hz, 3 ph.
M 45-C0330/Z
Same as above but 110 V, 60 Hz, 1 ph.
sCode D.C.D.M.A. Ø specimen
mm inches
45-C0343
AX
30.10 1.185
45-C0344
1.5 in.
38.10 1.500
45-C0345
BX
42.04 1.655
45-C0346
NX
54.74 2.155
General description and specifications
This rock and masonry saw has been specially developed to cut rock or core samples. The machine is supplied complete
with a special clamp to allow irregular
specimens to be held firmly in place during
the cutting operation. The machine can
accept blades up to 450 mm dia. Supplied
complete with base frame, water pump and
“V” shaped cylinder clamp. The blade must
be ordered separately (see accessories).
Cutting depth (mm): 115 mm with 350 mm
dia. cutting blade and 165 mm dia. with
450 mm dia cutting blade.
Power: 2250 W
B Dimensions:
with base 1200x800x1400 mm
A Weight approx.: 125 kg
General description and specifications
This machine is specifically used in the
laboratory for cutting core samples from
hard material such as rock and concrete.
A clamp is provided to firmly secure the
material during the cutting cycle. A special
tool is also available (see accessories) to
prepare rock samples from core pieces.
Drile bits not included. See accessories.
Power unit: 1800 W
Coring speed: 1485/2720 r.p.m.
Coring range: dia. 8 – 60 mm
B Dimensions of the base tray assembly:
450x450x300 mm approx.
A Weight approx.: 80 kg
45-C0331
Accessories
Accessories
s45-C0211/4
Diamond blade 350 mm dia. for rock
specimens
s45-D1717
Clear safety goggles
s45-C0331
Clamping device for cores max. dia.
100 mm complete with transparent
protection
s45-C0343 to 45-C0346
Drill bits and spigot adaptors
45-C0330 with
core bit taking
sample from a large
rock core
45-C0330 with core
bit taking sample
from a large stone
Transparent
acrylic protection
45-C0210/C with 45-C0211/4
Testing equipment for the construction industry
169
45
ROCK TESTING
Sample preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Speciment grinding/ Dimensional Verification
 Specimen grinding
 Specimen dimensional verification
q STANDARD
q STANDARD
EN 12390-2,
ASTM D4543
ASTM D4543, ISRM Sugg. Method
M 45-D0539
Rock sample verification apparatus
M 55-C0201/B
Specimen grinding machine.
220-380 V, 50 Hz, 3 ph.
M 55-C0201/BZ
Same as above but 220 V, 60 Hz, 3 ph.
General description and specifications
Used to grind and polish concrete specimens, natural stones, ceramic materials,
rock samples etc.
The cube cylinder and core specimens
can be easily locked on the table and the
grinding head 330 mm dia. can be radially
moved either manually or automatically
in both directions so the only manual
operation requested is the lowering of the
grinding head by the top hand wheel. The
machine is supplied complete with chip
guard, coolant tank, motor pump, one set
of abrasive sectors and instruction manual.
Diamond grinding sectors are available on
request (see accessories). The machine is
supplied complete with clamping element
for 100, 150 and 200 mm cubes. Clamping
devices for cylinders are also available on
request (see accessories).
The 45-D0534/B Core face preparation jig
can be easily fitted by the clamping element supplied with the machine.
General specifications
Table dimensions: 775x280 mm
Grinding wheel dia.: 330 mm
Max. vertical daylight: 350 mm
Min. vertical daylight: 145 mm
Max. specimen size: 200x200 mm cubes;
dia. 160x320 mm cylinders
Grinding wheel speed: 1400 r.p.m
Automatic cross feed in both directions
Safety guard with door locking switch
Grinding spindle motor power: 1,900 W
Feed motor: 110 W
Pulp motor: 100 W
Total power: 2200 W
B Overall dimension: 1200x1020x1640 mm (lxvxh)
A Weight approx.: 350 kg
A Weight approx. with packing: 415 kg
170
55-C0201/B
Accessories and Spare parts
s55-C0201/B1 Spare Set of 10 abrasive sectors
s55-C0201/B2 Spare Set of 10 diamond impregnated sectors
s55-C0201/B3 Accessory to connect
an aspirator for dry grinding procedure.
Aspiration not included
s55-C0201/B4 Clamping device for
cylinders from 100 to 160 mm dia.
s55-C0201/B5 Clamping device for
cylinders from 50 to 100 mm dia.
M 45-D0534/B
Core face preparation jig
General description and specifications
For preparation of parallel and flat core
faces using horizontal surface grinders
(e.g. 55-C0201/B). Consisting of a 4 place
locking device capable of clamping core
samples from 20 to 55 mm dia. It can be
mounted on most grinding machines with
or without magnetic chuck.
A Weight approx.: 6 kg
45-D0539 with a supplementary
82-D1250 gauge
General description and specifications
Used to verify the dimensional and shape
tolerances of rock core specimens up to 50
mm dia. by 100 mm length. The straightness
of the cylindrical surface can be easily verified
by the top dial gauge as well as flatness and
verticality of end surfaces by the same dial
gauge fitted to the lateral magnetic articulated dial gauge holder.
The apparatus comprises a base support with
column and dial gauge holder that can be
adjusted precisely vertically, a precision dial
gauge 5x0.001 mm, a “V” block, a magnetic
articulated dial gauge holder and small circular magnets to fit the “V” block on the base.
Support base dimensions:
135x170x250 mm
Column height : 200 mm
“V” block dimensions: 45x45x100 mm
Dial gauge: 5x0.001 mm
A Weight approx.: 8 kg
Accessories and spare parts
45-D0534/B
Testing equipment for the construction industry
s82-D1250 Dial gauge 5x0.001 mm
ROCK TESTING
. . . . . . . . . . . . . . . . . . . Strength and deformability tests
45
Uniaxial and triaxial test
Strength and deformability tests
Most of the information obtained
from laboratory tests are substantially related to the stress and
strain characteristics of the tested
materials.
The tests generally performed on
cylindrical rock samples are the
following:
- Evaluation of the compressive
strength and strain in uniaxial
conditions
- Evaluation of the compressive
strength and strain in triaxial
conditions.
Triaxial test on rock materials with measurement of axial strains
Typical Failure Envelope (diagram τ νs. σ)
 Uniaxial test
 Triaxial test
q STANDARD
q STANDARD
ASTM D3148, D2938
ISRM: Suggested methods for determining
the uniaxial compressive strength and deformability of rock materials
ASTM D2664, D5407
ISRM: Suggested methods for determining
the strength of rock materials in triaxial
compression
The uniaxial test is performed applying
an increasing load at a constant rate of
stress between 0.5 and 1.0 MPa/s. Axial
and radial strain are measured with high
sensitivity (about 5x10-6). Subsequent loadunload cycles are also carried out to obtain
a correct evaluation of the compressibility
properties.
The triaxial test is performed on test rock
samples, contained in a rubber sealing
membrane, placed within a triaxial chamber and subjected to an isotropic pressure
(generally between 5 and 60 MPa), kept
constant during the test. An axial load is
subsequently applied; tests and measurements are carried on in the same way as
for uniaxial tests.
-
From the measurements recorded during
the test the following information is obtained:
Rate of stress versus axial and radial strain
Maximum or failure stress
Tangent and secant Young’s modulus measured on the stress-axial strain curve
Rate of radial strain versus axial strain to
obtain the Poisson’s ratio
Maximum stress versus applied cell pressure (in the triaxial tests) to define the failure
envelope and the corresponding properties
(cohesion and friction).
Another important parameter investigated
in the triaxial tests concerns the permeability characteristics of rocks and rock
behaviour when subjected to high water
pressure, especially for the study of dam
foundations, and generally for underground tunnels and cavities.
Triaxial test on rock materials with measurement of axial strains
Typical Peak Strength Envelope (diagram σ νs. σ )
1
3
Testing equipment for the construction industry
171
45
ROCK TESTING
Automatic test systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . Main features of the complete
system
- Automatic Uniaxial and Triaxial
compression tests
- P.I.D. closed loop control
- Control up to 4 different
hydraulic frames
- Tests performed under control of:
- Load/Stress
- Displacement
- Strain
- Easy access to graphical and
numerical monitoring in real
time of all the measurements:
axial load and displacement,
cell pressure, axial and horizontal strain
- Automatic control of
cell pressure for triaxial tests
- Particularly suitable for
investigation of the past
failure behaviour of rocks
(displacement controlled tests)
- Real time variation of the
settings, including the control
method (load, displacement
or strain)
50-C5902/FR Frame with Hoek cell, 50-C9842 ADVANTEST 9, 45-C7022/S SERCOMP 7, and 86-D2999 PC cabinet
 Determination of Elastic Modulus
- Hoek triaxial cell to be selected conforming the specimen size (Triaxial tests
only)
- Strain gauges and accessories
- Test software.
q STANDARD
Operating principle
and strength characteristics
of rock specimens in uniaxial
and triaxial conditions
ASTM D2664, D2938, D3148, D5407, ISRM
Sugg. Method EN 14580, EN 1926
Introduction
Controls rock mechanics automatic test
systems are designed to test various materials from soft sandstone to high strength
basaltic samples. The complete test system
includes:
- Servohydraulic control console for
load application conforming the relevant
standards (see ADVANTEST code
50-C9842)
- High stiffness testing frame to be
selected conforming to the size of
the sample and the expected strength
(see load frames from 50-C4600/FR to
50-C6600/FR model page 238)
- Servohydraulic control console for
lateral pressure control (see SERCOMP 7
code 45-C7022/S). This unit which is derived from the standard SERCOMP 7 code
50-C7022, has been specifically designed
for rock testing (Triaxial tests only)
172
According to the reference standards,
during the test the compression load on
the rock specimen shall be applied continuously without shock, in such a manner
to produce a strain rate as constant as
possible, so that failure will occur within
5-10 min of loading or alternatively at a
constant rate of stress, within the limits
of 0.5-1.0 MPa/sec. Moreover, for triaxial
tests, the confining pressure has to be
maintained constant to within ± 1%. Our
new System has been designed to completely fulfil these strict specifications of
the test procedures. The ADVANTEST 9 is
driven by a sophisticated micro-processed
servo-control and both uniaxial and triaxial tests can be carried on at very stable
rate of stress, displacement or strain. The
SERCOMP 7 provides the automatic control
and managing of cell pressure within the
limits prescribed by the Standards. Strain
measurements are performed by means of
strain gauges applied directly to the specimen, both in axial and radial direction,
Testing equipment for the construction industry
so that Poisson’s ratio and compressibility
parameters are easily and properly evaluated during the test.
Axial load and cell pressure are also monitored by means of load cells and/or pressure transducers at high levels of sensitivity
and accuracy.
All the test data are graphically displayed
in real time, and stored in ASCII files for
further analysis with appropriate software
packages.
Note. For a complete list of suggested
items to perform Triaxial and Uniaxial test
see Table on page 177.
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic test systems
45
Determination of Elastic Modulus and strength characteristics
of rock specimens in uniaxial and triaxial conditions (continued)
Trixial test on rock core with measurement
of vertical stress, axial and circumferential
strain and confining pressure.
N O T E
General specifications of the SERCOMP 7 and ADVANTEST 9 consoles
(For more details and specifications see pages 241 and 247)
Sercomp 7 45-C7022/S
Advantest 9
50-C9842
Hydraulic port 2*
Power W
750
Max. working pressure, bar 600
Test performance
with PID closed loop control
Resolution
up to 1/65000
Current specs.
230 V, 50-60 Hz, 1 ph.
or 110 V, 60 Hz, 1 ph.
(please specify)
470x410x1000
120
Overall specs. mm (lxdxh) Weight approx. kg
4*
750
700
with PID closed loop control
up to 1/262000
230 V, 50-60 Hz, 1 ph.
or 110 V, 60 Hz, 1 ph.
(please specify)
470x410x1000 + PC
140 (including PC and printer,
which are supplied with the unit)
*The SERCOMP 7 and ADVANTEST 9 consoles can control respectively from to 2 up
to 4 loading frames for compression and/
or flexural tests on cement and concrete
(see page 241 and 247)
Detail of rock sample fitted with strain gages
Advantest 9:
An advanced flexible testing
system ideal for standard and
advanced automatic tests
on construction materials
• P.I.D. Closed loop control
• Control up to 4 different hydraulic
frames
• Perform tests under control of:
- Load/Stress
- Displacement
- Strain
• For connection of pressure transducer,
load cells, displacement and strain
transducers
• Particularly suitable to test
Deformability and Ductility (from postpeak test path) of:
- Rock samples
- Fiber reinforced concrete
- Shotcrete
- Concrete with polymer
fibre lining
• High flexibility: can control very low
capacity hydraulic frames up to 5000
kN
• Advanced
Quality-Performance/Price ratio.
The system is fully described on page 247
Testing equipment for the construction industry
173
45
ROCK TESTING
Automatic test systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . - Load and displacement
- Cell pressure (triaxial test only)
- Axial or radial strain (single strain
gauge or average).
- Easy calibration procedure and control
- Store of recorded data in ASCII file
- Direct access during the test to the list of
the data recorded from the beginning
- Possibility to pause the test, change setup and continue with the new parameters.
 Uniaxial and triaxial tests:
Test software
- Set-up of load/displacement/strain ramp
and cycles
- Diagrams in real time of:
- Stress, displacement, average or single
strain vs. time
- Stress vs. displacement
- Stress vs. strain
- Multi-diagrams display.
- Display in real time of recorded data:
Processing and printout
We propose two MS EXCEL data sheets
that, by the readings of the ADVANTEST 9,
perform:
- Uniaxial tests
- Stress-strain analysis
- Poisson ratio vs. strain plot
- Secant and tangent modulus calculation
- Triaxial tests
- Stress-strain analysis
- Poisson ratio vs. strain plot
- Failure envelope analysis.
 Uniaxial test
150
100
50
0
3
1.
5E
-
3
1.
0E
5E
.5
-0
-
3
3
Axial Strain
E-
3
-1
.0
E-
3
-1
.5
E-
3
.0
E-
2
-2
-2
.5
E-
2
E.0
-3
-3
.5
E-
2
Diametral
m
SStrain
0.
Force (kN)
400
350
300
250
200
Strain (mm/mm)
Uniaxial test: the test is performed on a cylindrical rock core with strain sensors measuring
the vertical and diametral strain
Uniaxial test: detail of rock sample fitted with 3
strain gages 82-P0392
Uniaxial test: example of printout
ε µε
1
ε
µε
3
P
kN
σ –σ
MPa
1
3
ν
-
Uniaxial test on a cataclasite rock specimen.
The vertical cracks are typical of the post peak.
Including No.3 Transducer holders 82-D1260, No.3
Transducers 82-P0331/C and Electric mean device
82-P0331/2
174
Testing equipment for the construction industry
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic test systems
45
Determination of Elastic Modulus and strength characteristics
of rock specimens in uniaxial and triaxial conditions (continued)
 Triaxial test
Hoek cells for triaxial tests
The lateral pressure is increased by programming steps and the corresponding
axial load is determined. Substantially the
failure point is continuously varied by
changing the lateral pressure.
3
Hardened steel spherical seat
2
1
Rock specimen
Rubber sealing sleeve
7
Hoek cells for triaxial tests
Oil inlet
General description and specifications
Hoek triaxial cells are offered in four models
of different size; each one consists of the
following:
- A cell body 1, complete with two quick
release self sealing couplings, for the
introduction of the hydraulic oil and cell
pressure, and for air outlet and saturation of the chamber respectively.
- Two end caps 2, screwed into the cylindrical cell body.
- Upper 3 and lower loading caps 4 with
spherical coupling
- Two female spherical seatings 5 connected to the loading caps 3 and 4 for the
correct transmission of the axial load
from the loading frame of the compression machine to the specimen.
- A rubber sealing sleeve 6 to separate the
specimen from the cell fluid.
Although each sleeve can be used for several tests, an order of five spare sleeves is
recommended (see accessories).
Measurements of axial and radial strain are
carried out with the use of electric strain
gauges 7, both in vertical and horizontal
direction, directly glued on the lateral
surface of the specimen. The wiring connections are passed within the rubber
sleeve through the cell body and loading
cap. Each strain gauge must be connected
to a proper electric device (see 82-P0070/1)
to complete and balance the Wheatstone
bridge. The strain gauge measurements
can be performed by automatic testing
systems described on page 172 or by suitable Datalog described on page 178 The cell
pressure and saturation pressure for permeability tests are carried out by the use of
appropriate equipment (see page 181).
Strain gauges
6
Cell body
4
5
Hoek cells
sCode D.C.D.M.A.
reference
Specimen size
d x h (mm)
Weight
(kg)
45-D0553
45-D0554
45-D0555
45-D0556
AX
1.5 in.
BX
NX
30.10 x 60
38.10 x 75
42.04 x 85
54.74 x 100
2.50
4.00
6.50
13.00
213
264
263
304
(1) Specimen plus loading caps plus spherical seatings
Spare rubber sleeves
sCode 45-D0553/1 45-D0554/1 45-D0555/1 45-D0556/1 D.C.D.M.A. Specimen size
reference
d x h (mm) AX
1.5 in.
BX
NX
30.10 x 60
38.10 x 75
42.04 x 85
54.74 x 100
Hoek cells for triaxial tests
Accessories
45-D0556/A,
45-D0556/B
s45-D0556/A (1)
(1) Please refer to the right hand sketch to
define the number of required parts depending on the Hoek cell size.
Pair of load spreader for uniform load
distribution
Total height(1)
mm
45-D0556/H
s45-D0556/B (1)
Distance pad to reduce the vertical clearance of the compression machine
s45-D0556/H
Hoek cells holder
Schematic view of the Hoek cell with load spread
and distance pads within the compression platen
of the testing frame
Testing equipment for the construction industry
175
45
ROCK TESTING
Automatic test systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . Determination of Elastic Modulus and strength characteristics
of rock specimens in uniaxial and triaxial conditions/ Accessories
 Accessories for Hoek cells:
Rock sample extruder
M 45-D0577/A
Specimen extruder
Used to extrude the rock sample from its
jacket thus avoiding to empty the confining fluid. It consists of a steel frame with
a rack and pinion mechanism. Supplied
without adapters, which should be ordered
separately. See adapters set.
A Weight approx.: 11 kg
Extruder adapters set
Comprising back plate adapter, two support cell body and shaft head.
Adapter set code
45-D0577/1
45-D0577/2
45-D0577/3
45-D0577/4
For specimen size
AX
1.5 inch.
BX
NX
For use with cell
45-D0553
45-D0554
45-D0555
45-D0556
Weight
approx. (kg)
1.7
1.7
1.5
1.5
 compression device for uniaxial tests
45-D0577/A
 LINEAR PATTERN STRAIN GAGES
FOR UNIAXIAL AND TRIAXIAL TESTS
M 45-C9034
Compression device for rock core
specimens 50 to 55 mm dia., 100 to
110 mm high
M 45-C9098/D
Lower and upper platen compression device for rock core specimens
100 mm dia.
q STANDARD
ASTM D2938
The apparatus consists of a two-column
frame fitted with an upper platen with
spherical seat that moves vertically sustained by a spring. The lower platen is fitted
to the base.
Platen dimensions:
55 mm dia., 28 mm thick
Platen minimum hardness: 58 HRC
Resistance: 120 + 0.3 % Ohms
Warking temperature: -20 to + 80°C
M 82-P0390
Linear pattern strain gage, 9.53 mm
length
This device comprises a lower and upper
platen 105 mm dia., 55 mm thick, minimum
hardness 58 HRC and a clamping device to
fit the upper platen of the EN series compression machines 300 mm dia. The lower
platen can be easily centred on the piston
or on a suitable distance piece instead of
the standard compression platen of the
machine.
M 82-P0391
Linear pattern strain gage, 20 mm
length
A Weight approx.: net 5 kg
Accessories
M 82-P0392
Linear pattern strain gage, 30 mm
length
M 82-P0393
Linear pattern strain gage, 60 mm
length
M 82-P0399/A
45-C9034
Strain gage application kit.
M 82-P0398
Electric interface for connecting up to 4
strain gages to MCC8, ADVANTEST 9 and
DATALOG.
M 82-P0390/1
Contacts for strain gages. 176 pieces.
M 82-P0070/3
Vertical daylight: 112 mm
Total height: 250 mm approx.
B Overall dimensions:
145 mm dia. x 250 mm
A Weight approx.: 10 kg
176
Excel data sheet for stress strain analysis
and elastic modulus processing in uniaxial
tests. For printout of test data and processing the following diagrams: Stress Strain
curves with axial, radial and volume strain;
Secant and Tangent moduli vs. axial strain;
Poisson’s ratio vs. axial strain; Radial Strain
vs. axial strain.
45-C9098/D
Testing equipment for the construction industry
M 82-P0070/4
Excel data sheet for stress strain analysis
and failure envelope for triaxial tests. For
printout of test data and processing the
same data of the 82-P0070/3 data sheet
plus the following: Strength Values vs.
confining pressures and strength envelope;
Mohr circles and failure envelope.
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic test systems
45
Determination of Elastic Modulus and strength characteristics
of rock specimens in uniaxial and triaxial conditions/ Configuration of a complete testing system
Typical configuration of an automatic system for Uniaxial
and Triaxial tests on rock specimens
 PC Accessory
Reference Standards: ISRM Suggested methods; ASTM D2664, D2938, D3148, D5407
sCode
Description
Q.ty
Uniax.
Q.ty
Triax.
AXIAL LOAD UNIT
PC cabinet
M 86-D2999
PC cabinet for testing systems.
230 V, 50 Hz, 1 ph.
ADVANTEST 9 Servohydraulic control console 1
1
for load application
86-D2999
PC cabinet (optional)
1
1
50-C6600/FR 4000 kN cap. EN compression frame (other models available from 2000 to 3000 kN cap.
See page 238)
1
1
50-C0050/CAL Special calibration of load digital unit assuring Class 1 from 1% of full scale 1
1
50-C9086 (1) Distance piece dia. 200x100 mm
3
1
50-C9080 (1) Distance piece dia. 200x30 mm
1
1
50-C9082 (1) Distance piece dia. 200x50 mm
2
1
50-C9842
CONFINING PRESSURE UNIT
50-C7022/S SERCOMP 7 Automatic control console for /
1
/
/
1
2
HOEK CELLS (different sizes available, see page 175 We propose here NX model)
45-D0556
Hoek cell NX 54.7 mm dia.
/
45-D0556/A Pair of load spreaders
/
45-D0556/B Distance pad
/
45-D0556/1 Spare rubber membrane
/
45-D0577/A Rock sample extruder /
45-D0577/4 Extruder adapter set for NX specimens /
1
1
1
5
1
1
45-R0023
82-P0354
constant pressure system in triaxialload testing
Three-way connector
Pressure transducer 700 bar cap. STRAIN READING AND CONTROL (Select the suitable strain gauges
within the models listed below)
82-P0398
Electric device to complete and compensate up 82-P0399/A
82-P0390
82-P0391
82-P0392
82-P0393
82-P0070/3
82-P0070/4
to four Wheatstone bridges with ¼ or ½ bridge set up 1
1
Strain gage application kit
1
1
Strain gage, grid width 4.53x9.53 mm.
Pack of 10
1
1
Strain gage, grid width 3x20 mm. Pack of 10
1
1
Strain gage, grid width 2x30 mm. Pack of 10
1
1
Strain gage, grid width 1x60 mm. Pack of 10
1
/
Excel data sheet for stress-strain analysis and elastic modulus processing for uniaxial tests
1
/
Excel data sheet for stress-strain analysis and failure envelope for triaxial tests
/
1
86-D2999
This PC cabinet is a purpose built accessory
for use in many laboratory applications,
where a PC is required in a testing environment. It is designed to provide PC system
protection from airborne contamination
such as cement dust. Filtration is achieved
by two vented filters in the cabinet. The
monitor can be fitted on top of the cabinet
and three extractable shelves holds keyboards, printer and mouse.
B Overall dimensions:
A
500x550x915 mm (lxdxh)
Weight approx.: 55 kg
N O T E
In case of uniaxial test on high strenght specimens featuring
explosive failure it is suggested the use of distance pieces
complete with threaded centering pin which are identified by
the suffix / P. Example 50-C9086/P
Detail of rock sample fitted with 3 strain gauges
82-P0392
Testing equipment for the construction industry
177
45
ROCK TESTING
Semiautomatic test systems . . . . . . . . . . . . . . . . . . . . . . . Lateral pressure systems/ Stress and strain measurament
 Semi-automatic test system
q STANDARD
ASTM D2664, D2938, D3148, D5407
ISRM Sugg. Methods
EN 14580, EN 1926
Introduction
The Elastic modulus and strength characteristics of rock specimens in uniaxial and
triaxial conditions can also be determined
in the semiautomatic mode, combining a
semiautomatic compression machine with
a manual lateral pressure system and with
all the other accessories already listed for
the automatic system.
The basic apparatus should comprise:
- Compression testing machine of suf ficient capacity (e.g. our digital
model 50-C5632 3000 kN cap.) with additional pressure transducer
- Manual or automatic lateral pressure
system (e.g. our models 45-D0588 or
45-D7022/S Sercomp 7)
- Stress and strain rock measurement
device by electric strain gauges (e.g.
82-P0908/B Datalog with accessories, pressure transducer, electric strain
gauges, etc.)
- Hoek cell with distance pads and load
spreaders (e.g. 45-D0553, 45-D0556/A,
45-D0556/B, etc.).
The uniaxial test conforming to ASTM
D3148 and D2938 is performed without
the lateral pressure system.
In detail, all requested items, are listed in
the Table on page 179
 Manual lateral
pressure systems
50-C4622 with 82-P0908/B, 45-D0558,
Hoek cell and accessories for triaxial test
 Stress and strain measurement
and recording
M 82-P0908/B
8 channel automatic data acquisition and conditioning unit.
110-230 V, 50-60 Hz, 1 ph.
This system is used to measure stress and
strain characteristics of rock samples. In the
standard configuration 6 channels are set
for strain measurements with electric strain
gauges; 2 channels are set for load/pressure
measurements with transducers.
Supplied complete with RS 232 serial communication cable.
M 45-D0558
Low friction manual pressure
maintainer for lateral pressure in
the Hoek triaxial cells
Used for maintaining constant the desired
lateral pressure in the Hoek triaxial cells.
The unit comprises a hand pump connected to a special oil reservoir, a precision
pressure gauge, a pressure maintainer and
a flexible hose 3 m long with 90° quick
release coupling.
Max. working pressure: 70 MPa
A Weight approx.: 15 kg
82-P0908/B
178
Testing equipment for the construction industry
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . .Semiautomatic test systems
45
Elastic modulus and strength characteristics of rock specimens in uniaxial
and triaxial conditions. Configuration of complete testing.
General description and specifications
Hardware
Number of channels: 8
Sensors outputs:
- Vex 2V DC (common to all channels)
- compatible with Wheatstone full bridges
(4/4). For use with 1/4 and 1/2 Wheatstone
bridges, see accessory 82-P0398
Sensors inputs:
- 0-20000 microV
- sensors impedance from 100 Ohm to 10
kOhm
Real resolution: 32000 divisions
Sampling rate: adjustable up to 3 samples/
sec per channel
Data storage
User interface: membrane keyboard and
128x64 pixel graphic display
Communication ports: RS 232 for data
download to PC with Controls DATA soft
82-P0908/ SOF, CONTROLS D-TERMINAL,
Microsoft HYPERTERMINAL or equivalent
or for serial printer 82-P0172.
Power supply: 110-230 V, 50-60 Hz,
1 ph.
Dimensions: 320x250x110 mm (lxdxh)
Weight: 2.5 kg approx.
Typical configuration of a standard semiautomatic system for
Uniaxial and Triaxial tests on rock specimens
Reference Standards: ASTM D2664, D2938, D3148, D5407
ISRM Suggested method
sCode
Q.ty Uniax Q.ty Triax
Axial load unit and test frame
50-C5632
Semiautomatic compression testing machine, 3000 kN cap.
Digimax 3 dual channel data acquisition and processing system 1
1
50-C0050/CAL Special calibration of load digital unit assuring Class 1 from 1% of full scale 1
1
50-C9080
50-C9082
Distance piece dia. 200x30 mm
1
1
Distance piece dia. 200x50 mm
1
1
Confining pressure
45-D0558
Low friction manual pressure maintainer for lateral pressure
45-R0023
Three-way connector 82-P0354
Pressure transducer 700 bar cap. /
1
/
2
/
2
/
1
/
1
Distance pad
/
1
Spare rubber membrane
/
5
Rock sample extruder /
1
Extruder adapter set for NX specimens.
(For other sizes select the sui table adapter. See page 176)
/
1
Hoek cells (different sizes available, see page 175 We propose here NX model)
45-D0556
Hoek cell NX 54.7 mm dia.
45-D0556/A Pair of load spreaders
45-D0556/B
45-D0556/1 45-D0577/A
45-D0557/4
On-board firmware
- Digital calibration of channels with linear and polynomial mode
- Data storing can be activated from
remote with external trigger
- Independent storing of each channel with dedicated memory configurable
as roll-over
- Easy recall and management of stored readings
- Alarm threshold can be activated on
each channel
- Date and clock function
- Selection of the language.
Description
Strain reading and control
(Select the suitable strain gauges within the models listed below)
82-P0908/B
82-P0398
82-P0399/A
82-P0390
82-P0391
82-P0392
82-P0393
82-P0070/3
82-P0070/4
1
1
Electric device to complete and compensate up to four
Wheatstone bridges with ¼ or ½ bridge set up
1
1
Strain gauge application kit
1
1
Strain gauge, grid width 4.53x9.53 mm. Pack of 10
1
1
Strain gauge, grid width 3x20 mm. Pack of 10
1
1
Strain gauge, grid width 2x30 mm. Pack of 10
1
1
Strain gauge, grid width 1x60 mm. Pack of 10
1
/
Excel data sheet for stress-strain analysis and elastic modulus processing for uniaxial tests
1
/
Excel data sheet for stress-strain analysis and failure envelope for triaxial tests
1
8 channels automatic data acquisition and conditioning unit
Accessories
s82-P0908/SOF Datasoft software
and serial cable for PC connection
/
Main features:
-Displays readings on the PC screen both as numeric values and graphic plots (axes and scales adjustable)
-Performs statistical elaboration of groups of readings (min. value, max. value, average value, standard deviation)
-Saves measuring sessions generating files
-Allows data-files management
- MS Windows® 98/2000/ME/XP
compatible.
PC software sample screen
Testing equipment for the construction industry
179
45
ROCK TESTING
Classification tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Splitting tensile test/ Slake durability
 Splitting tensile test
of intact core specimens
q STANDARD
70-T0108/E equipped
with the 50-C9032 device
for splitting testing
of rock disk
ASTM D3967
Introduction
This test method has been developed to
measure the uniaxial tensile strength of
rock specimens by the diametral compression of a disk. The splitting tensile strength
is calculated as follows:
σ =
t
2
P
___ · _________
π
L· D
where:
P
maximum compressive force
L, D thickness and diameter of rock
disk.
The test specimens shall be a circular disk
with a thickness-to-diameter ratio (L/D)
between 0.2 and 0.75. The diameter of the
specimen shall be at least 10 times greater
than the largest mineral grain constituent.
A diameter of 54 mm (NX) will generally satisfy this criterion. We propose, as
an accessory to a suitable compression
frame, the 50-C9032 Compression device.
Considering the average splitting strength
value of different types of rock ranging
from 3 to 14 MPa, a load frame of 50 kN
max. capacity should be suitable.
A suitable testing machine is our Universal
tester 70-T0108/E, 50 kN cap. that can
operate either with load or displacement
control.
Our Sales Dept. is at your complete disposal
for any assistance you may need.
M 50-C9032
Compression/splitting device
for 54 mm dia. rock specimens
This apparatus can be used for splitting
tensile strength on rock disk 54 mm dia.
Platen dia. is 75 mm. Total height 188
mm.
 Classification tests:
Slake durability index
q STANDARD
ASTM D4644
M 45-D0546
Slake durability apparatus.
230 V, 50 Hz, 1 ph.
M 45-D0546/Z
Same as above but 110 V, 60 Hz, 1 ph.
M 45-D0546/Y
Same as above but 220 V, 60 Hz, 1 ph.
This test method has been developed to
assess the deterioration of rocks over a
period of time when subjected to water
immersion. The apparatus consists of a
motorised drive unit which is mounted on
a baseplate and which can rotate two or
four drums at a speed of 20 r.p.m. The tank
assemblies are filled with water to a level
20 mm below the drum axis. The test drums
are manufactured from 2.00 mm mesh,
140 mm dia. x 100 mm long.
A Weight approx.: 15 kg
Accessories
s45-D0546/1 Pair of mesh drums,
complete with coupling and tanks
A Weight approx.: 8 kg
45-D0546
180
General description and specifications
Testing equipment for the construction industry
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Permeability of rock
45
Costant pressure apparatus
 Permeability of rock.
Constant head type
Introduction
This test is performed to measure
the water flow through the rock
specimen contained in the Hoek
cell and subjected to high confining
pressure. The hydraulic gradient
within the rock sample is supplied
by a constant pressure apparatus
and the water permeating the sample is collected in a burette. A couple of end caps are also necessary to
fit the Hoek cell.
28-WF4312 with Hoek cell, permeability end caps, burette, support base and metal/glass sleeve
Typical configuration of a Rock permeability test set
 Constant pressure apparatus
sCode
M 28-WF4312
Oil and water constant pressure
apparatus for pressure up to 3500
kPa. 230 V, 50 Hz, 1 ph.
Rock permeability within Hoek cells
28-WF4312 Oil and water constant pressure apparatus for pressure General description and specifications
This apparatus provides an infinitely variable constant pressure and is used in conjunction with the Hoek cell fitted with the
permeability end caps, for the investigation
of the permeability of rock at high confining pressures in the laboratory.
The apparatus comprises: motorised
hydraulic pump; honed piston/spring
assembly; precision test gauge 0-3500
kPa range; cylindrical oil/water interchange
vessel; valves; 2 kg of high viscosity oil.
Description Q.ty
1
up to 3500 kPa. 230 V, 50 Hz, 1 ph.
28-T0490
Nylon tubing 6x4 mm dia., 20 m coil
1
45-D0556 (1) Hoek cell NX size
1
45-D0556/3 (1) Permeability end caps for NX Hoek triaxial cell 45-D0556. 1
Set of two
86-D1160 (1) Graduated glass burette 25 ml cap. x 0.1 ml div.
1
86-D1445
Support base 200x130 mm complete with rod 10 mm dia. 1
x 500 mm long
86-D1451
Double sleeve metal/glass 1
45-D0558 (2) Low friction pressure maintainer or
1
45-C7022/S (2) Automatic control console for constant pressure system 1
in the Hoek triaxial cell. 230 V, 50 Hz, 1 ph.
(alternative to 45-D0558, suggested for long term tests)
(1) Or other sizes (2) Normally required/available for the triaxial test (see pages 178 and 241)
Pressure range: 0-3500 kPa
B Dimensions: 310x300x390 mm
A Weight approx.: 16 kg
Accessories
s28-WF4191
45-D0558
45-C7022/S
Connecting hose to the Hoek cell
Permeability end caps
Glass burette and accessories
s28-WF4302/1
s45-D0553/3
s86-D1160
High viscosity oil. 5 l can
Permeability end cap AX size
s45-D0554/3
Graduated glass burette 25 ml cap. x 0.1
ml div.
Permeability end cap 1.5 in. size
s86-D1445
s45-D0555/3
Permeability end cap BX size
s86-D1451
s45-D0556/3
Permeability end cap NX size
Support base 200x130 mm
Double sleeve metal/glass
Hoek cells (see page 175)
Testing equipment for the construction industry
181
45
ROCK TESTING
Behaviour of joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Behaviour of joints
Typical roughness profiles
Another important section of rock
mechanics involves the study of
durability and discontinuities within
the rock mass, where the compression and shear strength is lower.
The behaviour of joints is particularly investigated: they are originated from geological failures, breaking off the rock mass continuity,
along which no sliding mechanism
is shown.
From the rock mechanics point of
view the discontinuities are characterised by mechanical strength lower
than the original rock matrix and
require detailed test investigations.
Strength of the joint walls
It is conventionally investigated with the
Schmidt Hammer (L model). A series of 10
measurements is performed both on the
joint walls and on a new failure surface.
From the 10 values obtained the 5 lower
are rejected and the compression strength
is given by the average value of the last
5. This parameter is generally indicated
as JCS (Joint Wall Compressive Strength),
expressed in MPa.
Surface roughness of the joint
This parameter is defined on the joint surface with the Barton comb (Profilometer
45-D0556) used to reproduce the roughness profile. The line obtained is compared
with a scale of roughness profiles, proposed by Barton, each of them is specified
with a classification number JRC, variable
from 0 to 20 (JRC = Joint Roughness
Coefficient).
Tilt test
An empirical method for an immediate
evaluation of the JRC index is obtained
with the tilt test (model 45-B0096). It
essentially consists of a horizontal plane,
upon which the two parts of the sample
are placed, laid one upon the other along
the joint surface. Then the plane is gradually tilted until the relative displacement of
the upper piece of the sample on the lower
one is observed.
The equipment is fitted with a lower edge,
to stop the lower specimen from sliding,
and one goniometer. The tilting angle
measured is related to the JRC index with
the following:
182
α - ϕR
JRC = ______________
Log (JCS/σ)
ϕR angle of residual shear friction (obtained from the shear test)
σ normal pressure acting on the joint
surface, generated by the weight of
the upper piece of the sample
JCS joint resistance (measured with the
Schmidt Hammer)
Shear strength of the joint
It is obtained from the direct shear test.
The peak resistance of a rough joint is
calculated from the following relationship
(Barton, 1973):
τ = σ · tg (ϕ + ieff) with
JCS
ieff = JRC · log ______
σ
Testing equipment for the construction industry
Therefore the shear test is performed:
- on a smooth joint to directly obtain
the shear friction angle ϕ
- on a rough joint to calculate ϕ from
JCS and JRC.
From the above expression it is interesting
to observe that, when the normal stress σ
equals JCS (compression strength of the
joint itself), i becomes 0. The mechanical
explanation is that, when the joint walls are
fractured for the applied high normal pressure, the shear resistance of the rock only
depends from the shear strength angle
ϕ and not from the surface roughness of
the joint.
For the measurement of the residual shear
strength of the joint the direct shear test
is also used. The mathematical expression representing the behaviour of residual
strength is the Coulomb’s linear failure
envelope without cohesion:
eff
τ = σ · tg ϕR
ROCK TESTING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Behaviour of joints
45
Measurement of shear strength
Roughness measurement. Profilometers / Tilt test
 Measurement of shear strength
q STANDARD ASTM D5607 (1)
ISRM: Suggested method for determining
shear strength (1974)
(1) To perform the test conforming to
ASTM standard, four dial gauges for vertical displacement are requested. See accessory 45-D0548/10
M 45-D0548
Rock shear box apparatus.
Hand operated
General description and specifications
This apparatus was originally developed at
Imperial College, London, by Professor E. Hoek.
It is a simple and practical method of determining the strength and slope stability of
rock, both in the field and in the laboratory.
The apparatus consists of a shear box designed to accept rock samples not larger than
115x125 mm, or alternatively cores up to 102
mm dia. The shear box consists of two halves,
the upper being connected to two rams for
reversible shearing action and the lower connected to a ram for normal load application.
The loads are recorded by Bourdon tube load
gauges.
The normal loading system is complete with
an adjustable low friction pressure maintainer
to absorb volume changes of the specimen
during the shearing action and to ensure a
constant vertical stress.
The apparatus is supplied complete with two
50 kN pumps and manometers and two
mould forms used for the correct alignment
of the sample before the test with cementation.
Gauge range: 50 kN x 1 kN
B Dimensions: 460x250x600 mm
A Weight approx.: 45 kg
Accessories
s45-D0548/9 High alumina cement
for the cementation of the sample in
the shear box. 50 kg bag
s82-D1257 Dial gauge 30 mm travel
for horizontal displacement x 0.01 mm
s45-D0548/10 Set of 4 dial gauges
10x0.002 mm complete with mounting
brackets
Spare parts
s45-D0548/8 Mould former
One of the pumps is
fitted with a pressure
maintainer to assure
auniform load during
the test
45-D0548
 Tilt test
M 45-B0096
Apparatus for measurement of the
joint roughness coefficient (Tilt Test)
Detail of the shear box apparatus fitted with the
45-D0548/10 accessory to perform the test conforming to the ASTM D5607 standard
 Roughness measurement.
Profilometers
Used for measurement of the roughness
profile of rock samples.
45-B0096
M 45-D0566
Profilometer (Barton comb).
300 mm length
General description and specifications
A Weight approx.: 1 kg
M 45-D0566/A
Profilometer (Barton comb). 150
mm length
A Weight approx.: 0.5 kg
45-D0566
It is used to calculate the JRC of a rock or
of a joint. The equipment consists of an
adjustable inclined plane, on which the
rock sample (100 mm dia. max.) is placed,
separated along the surface where the roughness is to be measured. Then the plane is
slowly tilted until sliding of the upper part
of the sample on the lower one occurs.
From the measured inclination angle it is
possible to evaluate the roughness index.
Inclination angle: 0-50°
B Overall dimensions:
265x170x260 mm
A Weight approx.: 4 kg
s45-D0548/1
Load gauge, range 0-50 kN x 1 kN
Testing equipment for the construction industry
183
45
ROCK TESTING
Classification tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Strength index/ Rock classification hammer
 Strength index
- Light and portable unit
- Sample size up to 102 mm dia.
- Accepts irregular shaped samples
- High resolution digital display
battery operated
- Resistant to failure shocks
- Serial port for PC connection
included
q STANDARD
ASTM D5731 - ISRM: Suggested method.
M 45-D0550/E
Digital rock strength
index apparatus (Franklin Press)
General description and specifications
The apparatus consists of a load frame 60
kN capacity with a hydraulic loading ram
actuated by a hand pump. The frame is
adjustable to allow for testing sample up
to 102 mm dia. A ruler assembled on the
frame allows for direct measurement of
the distance D between the conical platens
before and after the test. The compression
load is measured by a pressure transducer
with an advanced digital display unit assuring the best accuracy and resistance to the
failure shocks. The machine, fitted with the
accessory 45-D0550/D5, can also be used for
compression tests on small cores or cylindrical specimens. The apparatus is contained in
an easyly transportable plastic case.
Load range: 0-60 kN
Digital display: 2x16 characters
Resolution: 32.000 div.
Load pacer included
Load measured in both kN and MPa
Serial port for PC connection
Accuracy: ± 1%
Case dimensions: 800x500x280 mm
Weight: 15 kg approx.
Accessories
s45-D0550/D5 Set of lower and upper
platen 52 mm dia. with spherical seat
for compression tests
s45-D1717 Clear safety goggles
Spare parts
s45-D0550/A7 Set of hardened conical
platens
s45-D0550/A8 Set of gaskets for cylinder and pump
45-D0550/E
 Compression strength
q STANDARD: ASTM D5873
ISRM: Suggested method
M 45-D0561
Rock classification hammer
(Schmidt hammer – Low impact
energy model)
General description and specifications
Used to measure the rebound index on rock
cores and samples. The apparatus is simple,
easy to use, and is similar to the one used
for testing concrete. The level of impact
energy only is different: 0.74 Nm. Rock cores
are positioned horizontally and the rebound
index is obtained from the average of several
measurements performed perpendicularly
to the longitudinal axis. The unit is supplied
complete with carrying case.
B Dimensions of case:
78 mm dia. x 335 mm
Accessories
M 45-D0562/A ASTM rock cradle
Universal model, can hold all standard rock
core sample from EX to NX size (21.46 to
54.74 mm dia.) and even more. The apparatus comprises a vertical hammer guide
fitted to a steel plate of minimum mass
conforming to ASTM D5873, and a magnetic “V” block that can be easily fitted to the
steel plate.
B Dimensions:
220 mm dia. x 420 mm high approx.
A Weight approx.: 27 kg
184
Testing equipment for the construction industry
M 58-C0184
Calibration anvil
q STANDARD
EN 12504-2
ASTM C805, D5873
Used for calibration of concrete test hammer (models 58-C0181/N) and Rock classification hammer (model 45-D0561). Made
of special alloy steel and supplied complete
with traceable hardness certificate. It is
essential for the periodical laboratory verification of the Rock classification hammer.
B Dimensions:
150 mm dia. x 230 mm height
A Weight approx.: 16 kg
45-D0561
with 45-D0562/A