HM-59 and HM-73 Bending Beam Rheometers (BBR) by ATS measure the flexural creep stiffness of asphalt binder from ambient to -40°C to predict low-temperature thermal cracking of asphalt pavements. Special molds form small beam samples of binders for testing, and the deflection of the beam is recorded as a constant load is applied. Load, displacement, and bath temperature are displayed in real-time via tabular and graphic forms.
Both models use an air bearing system to assure reliable loading with accurate and repeatable results. A linear variable displacement transducer (LVDT) with a range of 6.35mm and accuracy to ±2µm measures deflection. The stainless steel three-point bend apparatus is easily removed and reinstalled in the base unit for convenient sample preparation and loading.
A fluid bath controls the temperature of the Ethylene Glycol/Water/Methanol mixture down to -40°C (-40°F). Process temperature is controlled by two independent platinum RTD temperature transducers to maintain stability. Both models fully comply with ASTM/AASHTO requirements. A source of clean, dry, compressed air at 50 PSIG minimum must be provided by the user.
Models come with five aluminum specimen Molds with mylar strips, a Calibration Kit with required weights, and Confidence Beam. Calibrated test weights and a certified LVDT NIST-traceable standard are also provided.
HM-59 ATS Bending Beam Rheometer operates through an included desktop computer system with pre-loaded control, data acquisition, and analysis software. The computer system includes monitor, keyboard, and mouse. Safe, rapid cooling of the test fluid is provided by the mechanical refrigeration system.
HM-73 ATS Touch Screen Bending Beam Rheometer retains all of the performance features of the HM-59 but incorporates a state-of-the-art touch-screen design for easy setup and operation. The touch-screen controller has walk-through menus for guidance and the machine can be started, stopped, and monitored remotely through an App installed on a smartphone, iPad, or tablet. The user-friendly control, acquisition, and analysis software is preloaded on the internal computer and allows daily verification and periodic calibration of the load cell, LVDT, and RTD transducers. A USB port is located on the front of the unit for software upgrades and data storage.
- Both models are fully compliant with ASTM and AASHTO requirements
- The optimal solution for predicting low-temperature thermal cracking of asphalt pavements via flexural creep stiffness measurements
- Air bearing systems ensure repeatable results and reliable loading
- Fluid baths accurately control the temperature of the Ethylene Glycol/Water/Methanol mixture down to -40°C (-40°F)
- ATS Bending Beam Rheometer with the pre-loaded computer (115V/60Hz or 230V/50Hz), or
ATS Touch Screen Bending Beam Rheometer (115V/60Hz or 230V/50Hz)
- Five aluminum specimen molds with mylar strips
- Calibration Kit with required weights and Confidence Beam
- Calibrated test weights
- Certified LVDT NIST-traceable standard
- HMA-348R Aluminum BBR Beam Molds used in cold temperatures to measure flexural creep stiffness of asphalt binder
- HMA-347 Mylar Strips adheres to the BBR mold and allows for easier sample extraction after testing