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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 |
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-100-2A DIGITAL
AND A GREENLEE HYDRAULIC PUMP
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November 27, 2007
Author: William W. Stump III
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. |
NOTE:
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.
You have a machine
with a piston on the top of the loading
frame, center the specimen on the
top platen. |
This is very important
if you want accurate testing results!!!
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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-100-2A
indicator.
This indicator allows for entry of specimen
dimensions, this will allow you to show
your loading rate in Stress/sec if the rate
of loading menu is set up for this function.
It is important to enter the proper specimen
dimensions prior to testing in order to
show the loading rate properly.
C-39 specifies the loading rate at 35 PSI/sec
+/- 7 PSI.
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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 Pump uses Dextron III ATF as the fluid
of choice.
The reservoir should be ¾ full of fluid.
The vent, located on the back of the
reservoir, should be open prior to testing.
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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. |
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
1.
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Put
the levers in a loading position. |
2.
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Pull
the RAPID TRAVEL lever towards you to raise the
piston until approximately ¼" of daylight exists |
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. |
4.
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Wait
3 seconds and Press the ZERO button on the digital
display |
5.
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WAIT
2 to 3 seconds until the load display blinks |
6.
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Rotate
the valve back to RAPID TRAVEL position and preload
the sample
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7.
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Rotate
the valve back to the METERED ADVANCE position |
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 |
9.
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IF
THE LOAD RATE DOES NOT SHOW ON THE BOTTOM OF THE
DISPLAY, DUMP THE PRESSURE USING THE DUMP VALVE.
DO NOT PROCEED WITH THE TEST. IF YOU DO THE PEAK
LOAD WILL NOT BE DISPLAYED AT TEST END. REPEAT
THE ZEROING PROCEDURE AT STEP 3 |
10.
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If
the rate of load shows up, follow the load rate
and keep it at 35 PSI/sec +/- 7 psi. |
11.
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You
may have to turn the star shaped knob on the flow
control valve CW if it is too fast or CCW if it
is too slow to achieve the proper speed. |
12.
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Once
you get your speed set, leave the star shaped
knob in that position. Continue to load the sample
until it fails. |
13.
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You
will notice the rate of loading will drop before
the sample fails. Do not attempt to compensate
during yield. |
14.
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Unload
the machine after failure by using the Release
lever on the right side valve |
You are now ready to test your next
specimen.
CALIBRATION
SERVICES, INC.
300 Buttertown Road
Emlenton, PA 16373
(724) 867-6664 or (800) 793-1870
FAX (724) 867-1346
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