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.