Field validation of constructed sub-grade and pavement. September 21, 2006. John S. Popovics Jeffery Roesler Marshall Thompson David Lange Robert Rodden Yi-Shi Liu Department of Civil & Environmental Engineering. Project Objectives.
September 21, 2006
John S. Popovics
Department of Civil & Environmental Engineering
Obtain response data and non-destructive test (NDT) test
results from a test structure that replicates the nominal design
to be used in the O’Hare modernization program.
10 inch pcc slab
16 inch dense AC base
NDT applied to determine in place thickness and/or material properties of pavement layers.
Impact-echo and surface wave methods (SASW, MASW)
Three types of sensors are embedded in the
On-site battery-powered data logger collects data
Instrumented concrete slab cast on June 22, 2006 at ATRELSensor layout (plan view)
Dowel barsJoint Opening Data
Expected resonance at 8000 Hz for 10 inch slab
Data from bonded regions (hollow points)
Data from dis-bonded regions (solid)
Inaccurate thickness predictions where pcc bonded to ac
Useful data for field verification of the constructed pavement layer have been collected. The sensor layout was effective. Most sensors functioned adequately, but lift-off sensor design should be improved.
Conventional NDT tests may not work suitably for OMP pavement structure (dense asphalt base)Work to date Conclusions
Continue sensing and data collection in trial slab
to monitor longer term environmental effects, and
share data with other OMP projects
Incorporate sensors (similar layout) in actual O’Hare
slab cast in 2007 (R/W 9L section?)
Modify or develop new NDT methods for estimation of
layer properties and thickness that will work on O’Hare
pavement: modified impact-echo and MASW. Tests
Developed at ATREL, verified at O’Hare