Abstract:
Most of the Departments of Transportation in North America are shifting its focus from
the construction of new roads to the maintenance and rehabilitation of existing
highways. Every year thousands of kilometers of road are being maintained or
rehabilitated in North America. So, there is a necessity to look for appropriate
strategies to maintain and rehabilitate the existing pavements. Many past studies
reported that the service life of overlay primarily depends on the interface bonding
between the existing pavement and overlay. In addition, the overlay fails predominantly
due to lack of proper maintenance for existing pavement surface before constructing
the overlay. In this paper, the Finite Element-based software program (ABAQUS) was
employed to evaluate the interlayer damages between the existing pavement and
overlay. A Box–Behnken Design (BBD) method is used to quantify the effects of
parameters such as the thickness of existing layer, thickness of the asphalt overlay,
modulus of asphalt overlay, modulus of existing rigid layer, rate of tack coating and
tining type on the performance of the constructed overlay. From the analysis, it was
found that, the performance of overlay predominantly depends on the strains inducing
at the interface between overlay and existing pavement due to traffic loads. Various
interface conditions are modeled for evaluating the performance of the overlay. The
results obtained from both the finite element analysis and BBD model could help in
selecting optimum tack coat application rate for existing pavement surfaces and for
developing a sustainable overlay construction specification.