Pavement Structural Analysis of the Design Recommendations for ...

Pavement Structural Analysis August 2004
Report No. 15953-2/1 ARA-ERES Consultants
1. Introduction
I-96 between M-39 and Schaeffer Road, just west of Detroit, Michigan, is planned for
reconstruction in 2005. The Michigan Department of Transportation (DOT) completed a
design for the reconstruction of this segment of I-96 in accordance with the 1993
AASHTO DARWin program. (1) Figure 1 shows the pavement design (material types and
layer thickness) resulting from that design procedure.
Mr. Curtis Bleech with the Michigan DOT requested that an analysis of that pavement
structural design be completed using a mechanistic-empirical method for a 20 and 40year
analysis period. The purpose of this document is to present the analyses completed
for evaluating the design pavement cross sections (material types and layer thickness)
recommended for the reconstruction of I-96 (refer to figure 1).
2. Study/Design Objective
The objective of this study was to analyze the flexible pavement layer thickness and
material types recommended for the segment along I-96 between M-39 and Schaeffer
Road using two mechanistic-empirical (M-E) design/analysis methods. One of the M-E
design/analysis methods was the same one used to prepare A Simplified Catalog of
Solutions, and the second one is the new M-E Pavement Design Guide developed under
NCHRP 1-37A. (2,3)
3. Project Design Parameters
3.1 Design Traffic
Pavement Structural Analysis of the
Design Recommendations for Reconstructing
I-96 (M-39 to Schaeffer Road)
The traffic parameters that were used to determine the design number of 80-kN (18-kip)
Equivalent Single Axle Loads (ESALs) in accordance with the 1993 AASHTO Design
Guide are summarized below and were provided by the Michigan DOT.
Average Annual Daily Commercial Traffic in 2005 = 9,600
Initial Annual ESALs, both directions = 2,382,720
Directional Distribution Factor = 0.56
Lane Distribution Factor = 0.70
Compound Commercial Traffic Growth Rate = 2.0%
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