Optimisation of the wheel tracking test time and result accuracy through computerised control
Wheel tracking is used to assess the resistance to rutting of asphaltic materials under conditions which simulate the effect of traffic. In this machine, two 500x180mm specimens are tested simultaneously by tracking with wheels fitted with pneumatic tyres under specified conditions of load, speed and temperature while the development of the rut profile is monitored at specified intervals during the test. The moulded specimens are inserted and removed from the wheel tracker using an Easy-load system.
The Wheel Tracker Large Device CRT-WTENLD supersedes the French Pavement Rutting Tester by using a unique instrumented measurement device, linked to the data acquisition, to measure the development of rutting during testing. It allows extreme efficiency compared to any other type of devices of its type. The test procedure and conditions are controlled and data acquired using Windows™ software running on a host computer via a high speed digital interface and signal conditioning system.
We have recently innovated Wheel Tracker Large Device and added two new exciting features:
Temperature recording and display
This new functionality in the software allows the operator to observe in real time a graph of the temperature as a function of time for each of the 4 probes (air and sample temperature for each side of the machine) from the start of the conditioning period until the end of the main test. Temperature data are also stored in a file for record keeping and analysis. Data are recorded at user-defined intervals, with a minimum interval of 30 seconds.
3-colour light system indicating the status of the computer
Controlling your time in a very active test lab environment divided over various tests and test devices is not always easy. We have incorporated a beacon on our Large Wheel Tracker to make life easier for laboratory operators. It clearly indicates the status of the test at a glance across the laboratory.
This beacon is essentially an efficient 3-color light system which works as follows:
• Red – Undergoing test cycles
• Amber – Take measurements reading
• Green – Test completed – machine stopped
This function allows the operator to work more effectively.
Standards
- EN 12697-22 Large device
- NF P98-253-1
