REHABILITATION WORKS IN QUEENSLAND USING FOAMED BITUMINOUS STABILISATION

Abstract

Adapting foamed bitumen stabilisation is considered as the most cost effective approach in
Queensland to expedite the rehabilitation works, especially after the major flood devastation in 2011. This
paper presents the key changes made as well as the recent practices adapted during a road rehabilitation work
to increase the return from the investment. In this process, initially, the designed width for subgrade lime
stabilisation has been modified to minimize the moisture entry into the pavement. The dry modulus, three days
soaked resilient modulus and retain modulus were used to identify the suitable base material for construction.
In addition, a trail site was used to examine the bulking effect on base layer when adding lime as secondary
agent, which helped to estimate the exact depth for foamed stabilisation. A few innovative techniques such as
a two-layer compaction to effectively condense stabilised subgrade, was used to improve the quality of the
outcome were also highlighted.