STATIONARY TEST TRUCKS RESULTS : KANSAS STATE STUDIES THE EFFECTS TRUCK AXLES HAVE ON PAVEMENTS

The accelerated pavement testing program at the Civil Infrastructure Systems Laboratory at Kansas State University is the first full-scale operation in the Midwest and is supported by four states. It is comprised of a truck axle forced by a hydraulic pump onto the test pavement as the axle is pulled back and forth in a pattern that simulates the lateral variations of actual driving. The speed is kept at a constant 10 mph to be low enough to cause creep loading. Dual axles are used in most experiments, with each half axle testing a different type of pavement, enabling simultaneous testing of two pavement structures. The lab can also subject the pavement to freeze- thaw cycles. Current research is examining the structural performance of recycled asphalt materials that have been stabilized with foamed asphalt. Early results suggest that it performs very close to conventional crushed stone.