Through
funding from the Illinois Department of Transportation, ATREL
acquired the Accelerated Transportation Loading System in 1993.
A $2 million investment, the ATLAS can evaluate full-scale transportation
systems subject to real life traffic and environmental loading.
The system is capable of simulating aircraft, truck, or rail traffic
distributions, testing all types of pavement systems, and applying
load levels exceeding that of highway and airfield limits.
ATLAS weighs 156 kips and is 124 feet long, 12 feet high, and
12 feet wide. Mounted on four crawler tracks, the test unit can
be easily positioned on the pavement test section. ATLAS transmits
loads to the pavement structure through a hydraulic ram attached
to a wheel carriage, which can accommodate a single tire, dual
tires, aircraft tire, or a single axle rail bogey. The load level
can vary between 0 and 80 kips. ATLAS is housed in a moveable
sprung structure that also controls the effects of daily temperature
and moisture changes on the pavement section being studied. The
ATLAS facility also has readily available data acquisition systems
for collecting both static and dynamic data from instrumented
pavement sections.
The loading length of the ATLAS is 85 feet with approximately
65 feet of constant velocity loading of the wheel. At a maximum
speed of 10 mph, loading can be either uni- or bi-directional.
It can also wander up to 3 feet in a lateral direction to simulate
real world traffic distributions. ATLAS can apply up to 10,000
repetitions per day. For a 20 kip single wheel load, trafficked
at the edge of a concrete slab, ATLAS can simulate approximately
5 million ESALS per day. |
