Accelerated Polishing Machine simulates aggregate wear on asphalt pavement caused by the action of vehicle tires. The machine is designed for the ASTM D3319 and AASHTO T 279 or BS 812/EN 1097-8 test methods.
Specimens are prepared by securing 3/8–1/2in (9.5–12.7mm) aggregate pieces into special curved molds with a bonding agent. Fourteen curved segments of specimens are clamped around a “road wheel” to form a continuous aggregate surface 1.75in (44.5mm) wide and 16in (406mm) in diameter. The road wheel is driven to loaded contact with a rubber-tired wheel while an abrasive and water are fed to the contact area. After polishing, friction values are determined using a Pendulum Skid Tester.
During testing, the road wheel is driven by an electric motor at 320 ±5rpm through an abrasive adjustable timing belt. The Goodyear 8in (203mm) diameter pneumatic-tire assembly maintains an 88lbf (391N) load on the road wheel while HMA-240 Abrasive Silicon Carbide Grit and water are distributed onto the test surface at a prescribed rate. Water is gravity fed from a tank through a calibrated flow meter and is collected with the used abrasive in a removable tray. Pneumatic tire assembly loads are controlled by a mechanical lifting device. Tests are automatically terminated by a preset revolution counter.
The Accelerated Polishing Machine consists of a welded steel frame on adjustable leveling feet and is supplied with two specimen molds, two mold plates, required feeders, wheel assemblies, wrenches, mounting pads, and operating instructions. Each ASTM/AASHTO test requires about 10lb (4.5kg) of silicon carbide grit (sold separately).
HM-614 models meet in accordance with ASTM D3319 and AASHTO T 279 test methods.
HM-615 models meet in accordance with BS 812/EN 1097-8 test method.
Models operate on either 115V, 60Hz, or 230V, 50Hz, depending on the chosen model. Product dimensions are 31.10x31.89x48.43in (790x810x1,230mm), WxDxH.
- An effective way to determine aggregate wear using vehicle tires
- Compliant with the ASTM/AASHTO and BS/EN test methods
- The revolution counter automatically terminates tests when completed
- Accelerated Polishing Machine (115V, 60Hz or 230V, 50Hz)
- (2) Specimen Molds
- (2) Mold Plates
- Required Feeders
- Wheel Assemblies
- Mounting Pads