*Copy this information as you might need to reference it as you go through the questions*
A local City in the eastern United States is planning to reconstruct 1.5 miles of a two lane roadway (25’ wide) in an urban area.  They have historically used standard pavement sections for different road classifications in the City.  The Director of Public Works recently attended a Tensar Road Show event and understands that it may be possible to optimize their standard pavement section using TriAx geogrid.

As the City’s engineering consultant, you are being asked to evaluate alternate pavement cross-sections incorporating TriAx and report on the benefits.  SpectraPaveTM software will be required to complete this design challenge.  Use default inputs unless otherwise noted below.

The following information is provided:

Standard Pavement Section
HMA Surface Course – 2.0” (layer coefficient = 0.42)
HMA Binder Course – 3” (layer coefficient = 0.36)
Aggregate Base Course – 10” (layer coefficient = 0.14, drainage coefficient = 1.0)

Reliability = 90%
Standard Deviation = 0.49
Subgrade Resilient Modulus = 6,000 psi
Initial Serviceability = 4.2
Terminal Serviceability = 2.0