The wheel tracking test is used for determining the susceptibility of Hot Mix Asphalt (HMA) to deform under load by measuring the rut depth formed by repeated passes of a loaded wheel at a fixed temperature. We also produce Wheel Trackers conforming to EN 12697-22 standard and a Universal version conforming to both AASHTO and EN Standards. See Double Wheel Tracker, EN versions and Universal AASHTO/EN Double Wheel Tracker.
Two versions are available with full access to the water bath or complete with clear trasparent sliding doors, water bath covers and automatic water filling and leveling system.
The DWT Hamburger type Double Wheel Tracker can be used as part of your Superpave performance based testing program.
Sheet steel, powder coated. Trasparent sliding door.
Loaded wheel system
The wheel load is 705 N. The system includes a motorized lifting system for raising the wheel assembly at the end of the test.
Wheel tracking carriage
The wheel is moved 230 mm backwards and forwards on the top of the slab, which is fixed. The speed is adjustable via the PC from 20 to 30 cycles per minute (40 to 60 passes). The longest slab dimension is oriented to the wheel's direction of travel. Special slab moulds for circular samples obtained from coring or gyratory compactors are also available. See accessories.
Temperature control system
The AASHTO Hamburg type Standard states that the test must be performed in a water bath with a temperature range of 258 to 70° ±1°C. A water level of about 20 mm above the sample has to be maintained. Where a heated air environment is specified, the specimen, during testing, must be maintained at uniform and constant specified temperature ± 1°C. The DWT Double Wheel Trackers fully satisfy and exceed the above requirements: the temperature accuracy is ± 0.5°C.
Impression measurement system
Each wheel is fitted with RUT DEPTH transducers for measuring deformationsfrom 0 to 40 mm ±0.01 mm.