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CALIBRATION
SERVICES, INC.
300 Buttertown Road
Emlenton, PA 16373
724-867-6664
ACCREDITED
724-867-1346 Fax
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Web: www.calibrationinc.com
Email: info@calibrationinc.com
ISO 17025-2005
Laboratory Accreditation Bureau
CERT # L 1174 |
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Specializing
in Service, Calibration, Retrofit, and Sales
of Physical Testing Equipment
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INSTRUCTIONS FOR TESTING
CONCRETE CYLINDERS USING A COMPRESSION
TESTING MACHINE WITH A CS-100-1BR DIGITAL
AND A GREENLEE HYDRAULIC PUMP
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November 30, 2007
Author: William W. Stump III
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1.
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Sample
Preparation
| Prepare the concrete sample
in accordance with ASTM C-39. |
Use the capping method
of choice.
If using pad caps, be sure to have the appropriate
durometer pads in the bases. |
| Be sure to thoroughly
clean the bases on a regular basis both
inside and out. Concrete debris will
build up on the inside of the steel bases.
This will cause excessive corner breaks
on samples if the debris is allowed to build
up. Use a blunt instrument to remove the
debris and reinstall fresh pads. |
| When using pad caps, the
rule of thumb is to break 100 cylinders,
flip the pads over test 100 cylinders and
throw the pads away. Typical life expectancy
of pads is 200 breaks. Over usage of
pads will cause unacceptable tests results. |
| When installing pad caps
on the specimen, always put the bottom of
the specimen in the bottom pad cap base.
The bottom of the specimen is the side which
sits in the bottom of the cylinder mold. |
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2.
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Preparing
for application of load to the sample
| Take your capped specimen
and insert it into the testing machine.
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| Center the specimen in
the upper and lower pad bases. |
Center the specimen in
the testing machine.
| If you have a machine
with a piston on the top of the loading
frame, center the specimen on the
top platen. |
| If you have a machine
with a piston on the bottom of the
loading frame, Center the specimen
on the bottom platen. |
This is very important
if you want accurate testing results!!!
Your testing machine will have a Digital
Display for load indication. |
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| Please review the features
of the Digital display before attempting
to test samples. This information is found
in the Digital Manual. |
Each model of digital offers
different ways to input critical information
regarding your test. If an authorized calibration
company is performing setup, please ask
to be instructed on digital operation and
features at time of setup. If this is not
the case….PLEASE READ THE MANUAL.
Your machine is fitted with a CS-100-1BR
indicator.
This indicator will show you force in Lbs,
N, Kn, and KG. Selection of engineering
unit is made by pressing the Enter key.
This display will show your rate of loading
during a test in the left hand column of
the display. The display will show your
force reading and peak load reading in the
right hand side of the display.
C-39 specifies the loading rate for 6 X
12 cylinders at 990 lbs per second +/- 200
lbs per second.
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3.
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Application
of Load
| Before applying load
to the specimen, it is very important to
understand the operation of the control
valves on the pump. |
| The machine in this example
has a Greenlee Hydraulic Pump with a Greenlee
flow control valve. |
The Pump
The valve contains 2 levers and 1 stem.
The lever on the right side of the valve
is the pressure/release lever.
The vent, located on the back of the reservoir,
should be open prior to testing. |
The Valve
The valve contains 2 levers and 1 stem.
The lever on the right side of the valve
is the pressure/release lever.
| In the upright position
(with the knob against the motor)
the pump will Build pressure. |
| In the down position
(with the knob against the reservoir)
the pump will release pressure and
allow the piston to retract. |
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The lever on the left is
the rapid advance/controlled rate lever.
| With the knob pull
toward the operator, and the release
lever in the pressure position, the
pump is in rapid advance. |
| This means the piston
will move rapidly. Care must be
taken when using the rapid advance
function. The piston only has
2 ½ inches of stroke. If left in the
rapid advance position for too long,
the piston will overextend causing
a release of oil from the piston area.
Immediately shut off the pump and
call CSI at 724-867-6664 for proper
instruction of how to eliminate this
problem. |
| The rapid advance
lever is used only to position the
piston close to the sample for zeroing
purposes, or to preload the sample
once zeroing has been performed. Never
use the rapid travel position to test
the cylinder to total failure. This
will provide inaccurate test results. |
| With the knob pushed
back toward the pump motor (all the
way back) the pump will be in the
controlled rate position. |
| All the fluid will
be sent through the stem located in
the center of the valve. This stem
will allow you to set the rate of
loading for the machine. |
| ASTM C-39, for a
6 X 12 concrete cylinder, requires
the rate of loading to be 35 psi/sec
+/- 7 psi. Calculated in lbs, this
comes out to 990 lbs per second +/-
200 lbs. |
| The stem in the center
acts like a water spigot. Counter-clockwise
increases the rate of force application
per second. Clockwise decreases the
rate. YOUR VALVE HAS BEEN LOCKED
IN THE PROPER POSITION FOR 6 X 12
SPECIMENS, |
| Once the proper rate
is achieved, you can leave the stem
at that setting and the machine will
continue to load at the proper rate. |
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YOU ARE NOW READY TO TEST YOUR
SPECIMEN
Turn on the pump
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1.
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Put
the levers in a loading position. |
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2.
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Pull
the RAPID TRAVEL lever towards you to raise the
piston until approximately ¼" of daylight exists |
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3.
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IMMEDIATELY
move the rapid travel lever completely toward
the consol to METERED ADVANCE position. DO
NOT MAKE CONTACT WITH THE SPECIMEN YET. If
you have then you must release the pressure and
go back to step 1. |
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4.
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Wait
3 seconds and Press the ZERO button on the digital
display |
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5.
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WAIT
2 to 3 seconds until the load display blinks |
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6.
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Rotate
the valve back to RAPID TRAVEL position and preload
the sample
Normally you should preload to about 15,000 lbs
or 20,000 lbs |
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7.
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Rotate
the valve back to the METERED ADVANCE position |
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8.
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Wait
for a second or two and view the load rate display
which is located directly under the load display
on the digital |
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9.
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If
the loading rate is too low or too high, you may
have to unlock the metered stem and turn the shaft
on the flow control valve CW if it is too fast
or CCW if it is too slow to achieve the proper
speed. The stem can be unlocked by loosening the
allen screw in the 5 o'clock position next to
the stem. |
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10.
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Once
you get your speed set, leave the stem in that
position and lock the valve down. Continue to
load the sample until it fails. |
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11.
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You
will notice the rate of loading will drop before
the sample fails. Do not attempt to compensate
during yield. Do not try to re-adjust the valve
after you have achieved 50% of the cylinders capacity.
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12.
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Once
the specimen has broken, move the lever on the
right (retract lever) all the way down to retract
the piston. Remove the debris and record your
peak value which will be on the right side of
the display. |
SPECIAL NOTE:
ONCE YOU HAVE GOTTEN A GOOD ZERO ON THE FIRST SAMPLE,
IF YOU HAVE OTHER SAMPLES TO TEST, YOU DO NOT NEED TO
ZERO THE DIGITAL EACH TIME.
THE ONLY TIME YOU SHOULD REZERO IS WHEN YOU START A
NEW TESTING SESSION OR AT THE BEGINNING OF EACH DAY.
You are now ready to test your next specimen.
CALIBRATION
SERVICES, INC.
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300 Buttertown Road
Emlenton, PA 16373
(724) 867-6664 or (800) 793-1870
FAX (724) 867-1346
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