CHAPTER 6
ANALYSES OF FIELD MEASURED NDT DATA
6.1 General
A complete description of the testing program has been presented in
Chapter 5. The results of the field measured Dynaflect and FWD data are
listed in Appendices A and B, respectively. These data were used with
the prediction equations presented in Chapter 4 to determine the moduli
of the pavement layers for the test sections. The analyses of the NDT
data with regard to determining the elastic characteristics of the test
pavements are presented in this chapter.
6.2 Linearity of Load-Deflection Response
The underlying assumption in the theoretical analysis for the
interpretation of NDT measurements is that each pavement layer acts as
an isotropic, homogeneous, and linearly elastic medium. For this
reason, a multilayered elastic computer program, BISAR, was used for the
simulation and development of NDT and pavement layer moduli prediction
equations, respectively. Therefore, the applicability of multilayered
linear elastic theory to the test pavements is verified in this section.
FWD measurements carried out at different load levels and tem
peratures provided the means of checking whether it was feasible to
adopt a linear elastic model to Florida's flexible pavement systems.
The plot of load levels versus FWD deflections is a simple way to assess
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