Direct Tension Tester


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The Interlaken Superpave Direct Tension Tester has been evaluated by the Federal Highways Administration and meets the
following specifications all AASHTO, SHRP and FHWA specifications. It is designed to perform asphalt binder tests in accordance with the AASTHO T 314 and ASTM
D 6723 test protocols.
This is a computer-controlled machine that features:
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Closed Loop Control and Data Acquisition Using Iterlaken UNITEST Control System Software
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Fully integrated Software Package
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Real Time Data Acquisition
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Manual or Automatic Test Capability
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Exlar actuator for Higher Accuracy and Dynamic Performance
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Temperature-Controlled Fluid Bath
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Choice of Chiller Options
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The Interlaken Direct Tension System for asphalt is a
complete instrument for evaluating stiffness and failure
properties of asphalt binders at low "in-service"
temperatures. (Use The Interlaken DT for AASHTO T 314).
Interlaken DT results, in conjunction with Bending Beam Rheometer (BBR) data, provide a more complete
characterization of the asphalt binder. In addition, Interlaken DT data predict the temperature at which thermal cracking would occur in the roadway.
The Interlaken DT features both the simplicity required of a routine specification tester for QA/QC and the versatility of a full research instrument, all in one. In fact, it is just as easy to determine the Pass/Fail analysis for asphalt Performance Grading as it is to perform comparisons of binder/additive and binder/modifier interactions over a wide range of strain rates. |
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The blister test is used to determine the adhesion strength of hot-poured crack sealant at the application temperatures.
The blister test is a test of fracture. The objective of the test is to inject alcohol between a substrate (aluminum plate) and hot-poured crack sealant in such a way that the sealant is detached from the substrate in the form of a blister. The energy balance principle is used to calculate the adhesive fracture energy, which is a fundamental and unique property of each individual interface. Pressure of the injected alcohol is measured using a pressure transducer, while the height of the blister in the center of the dome will be measured through an LVDT. Using the data collected from the test period and the energy balance principle, one can
calculate the adhesive fracture energy. |
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The adhesion test is a test of fracture. The object of the test is to apply tensile forces to the interface between sealant and aggregate. Sealant is confined between two half cylindrical aggregate (aluminum can be used for standard test). The applied force and displacement can be recorded as functions of time. Energy required to break the bond can be calculated by measuring the area under the load-displacement curve. This energy can be considered a measure of bonding. In addition, the maximum force to failure can be reported as adhesion strength. |
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System includes 6 asphalt specimen molds and 6 end tabs, developed for performing AASHTO TP314. Additional sets are optionally available.

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A verification spring along with stress-strain characteristics are provided with your Interlaken Direct Tension Tester. The verification spring is
provided to verify calibration of the load cell and displacement transducer at least every six months and when measurements are suspect.

Pictured above:: Verification spring
positioned in Direct Tension Tester.
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SPECIFICATIONS:
Maximum load: 500 N
Speed: 0.372 to 312 mm/min
Stroke: 75 mm
Temperature (std) Range: +6° to -25° C, other temperature options available to -40° C.
Temperature Stability: +/-0.1° C or better
Accuracy: Rate:
Force: +/-0.1% of setting
+/-0.5% of reading
(to 2% of capacity)
Power: 110VAC 60Hz 15 amps,
220 VAC,50Hz
DT Unit Dimensions:
Overall (LxHxW): 38"x27"x15"
Bath (LxW): 11"x11.5"
Control System/Desk Dimentions:
Overall (LxHxW): 46"x52"x30"
AASHTO 314 requires 20 mm travel with 1 micron resolution (4 *10E-5 in) and 500 N load. Test speed is 1mm / min.
Actuator: Exlar GSM20-0301
2048 count encoder
0.1In. lead
4.89*10E-5 in. / count
5 counts / sec minimum
Minimum Speeds
2.44*10E-4 in / sec minimum rate or 1.46*10E-2 in / min minimum
6.20*10E-3 mm / sec minimum rate or 0.372 mm / min minimum
10E6 counts / sec maximum (B&R)
Maximum Speeds
3000 RPM max speed, this requires 51 volts at no load.
Max RPM based on counts is 123
12.3 in / min max speed 312 mm / min max speed
0.2 in / sec max speed 5 mm / sec max speed
Note: Specifications are subject to change without notice
For Asphalt Testing
ALSO SEE!
INTERLAKEN'S
COMPACT SOIL &
ASPHALT TEST
SYSTEM