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 binder for testing, and 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 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. 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 set up 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 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
- 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 temperature of the Ethylene Glycol/Water/Methanol mixture down to -40°C (-40°F)
- ATS Bending Beam Rheometer with 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