The BBR asphalt low-temperature bending beam rheometer from Toyotest employs a new thermoelectric cooling technology, enabling rapid temperature reduction from room temperature down to -36°C with temperature control accuracy within ±0.03°C. The instrument’s deformation measurement accuracy reaches 0.155 micrometers, and its force measurement accuracy is 0.147 millinewtons (0.015 grams). The DF-BBR bending beam rheometer features a load range of 0–450 grams. The computer software boasts powerful functionality, allowing users to set test temperatures, customize test graphs, and save and print test data directly from the computer. The instrument is equipped with four gas pressure regulators, which can adjust the main line pressure, the gas bearing pressure, the pressure required to bring the loading axis to “zero,” and the actual loading pressure. A speed-adjustable magnetic stir bar circulates cooling fluid at the bottom of the cooling bath, ensuring uniform temperature distribution throughout the bath. This instrument complies with ASTM D6648, AASHTO, and SHRP provisional specifications for the bending beam rheometer test of asphalt binders.

　　 Use

　　The asphalt bending beam rheometer accurately measures the bending creep stiffness and creep rate curves of asphalt at low pavement temperatures, enabling the evaluation of asphalt’s low-temperature cracking performance. This primarily reflects its ability to resist temperature-induced shrinkage cracking and thereby prevent low-temperature pavement cracking. The instrument is suitable for both unmodified asphalt and modified asphalt; it can test virgin asphalt, asphalt subjected to pressure aging tests, and aged asphalt resulting from the rotating thin-film oven (or thin-film oven) test.

　　 Routine application

　　Flexural Creep Test for Asphalt Binders

　　Low-temperature performance of crack sealing under load application

　　Meets ASTM D6648, AASHTO T313, and

　　Low-Temperature Asphalt Binder in SHRP Asphalt Testing Specifications

　　Flexural Creep Test

　　 Product Features

　　Loading frequency ranges from static to dynamic at 25 Hz.

　　Uses an external Peltier system for direct thermoelectric cooling (fluorine-free).

　　Integrated freestanding bathtub that uses ethanol as the bath medium for cooling.

　　Set and monitor the water bath temperature via software control.

　　 Technical Parameters

　　Temperature range: Room temperature to -40℃

　　Temperature control accuracy: ±0.03℃

　　Temperature resolution: ±0.01℃, measured using an RTD platinum resistance sensor.

　　Bending deformation accuracy of the small beam specimen: 0.01 μm, resolution: 0.01 μm

　　Displacement sensor range: ±5mm

　　Displacement resolution: 0.05 μm

　　Load sensor range: ±25N

　　Load resolution: 0.05 mN

　　Modulus testing range: 20 MPa to 1 GPa

　　Loading frequency: From static to 25 Hz

　　Power supply: 90–264V, 50Hz/60Hz, 1-phase, 240W