Authors

Abstract

Base and Subbase layers are considered as the platform for distributing the
different applied stresses in flexible pavements. The two layers must provide
sufficient strength to resist any excessive generated deformation to achieve this goal,
proper compaction machinery is essential to reach the required degree of compaction.
The present paper investigates the influence of degree of compaction of the base
and Subbase layers on the generated deformation under the action of both monotonic
and cyclic loadings. Model tests were performed by compacting beds of base and
Subbase layers to relative densities of 65%,77% and 88%, inside steel container of
dimensions 1000mm*750mm*750mm. The final thicknesses of the base and Subbase
layers were 150mm and 350mm respectively.
A circular model footing of diameter 175mm: equivalent to 24194 mm tire
contact area is placed on the base layer and subjected to a series of monotonic and
cyclic loadings. The results of monotonic tests revealed an increase of 71% and 107%
in the carrying capacity when the relative density increased from 65% to 77% and
from 65% to 88% respectively.
The cyclic tests revealed a substantial increase in the number of cycles at any
stress level as the relative density increases from 65% to 77% and from 65% to 88%.