The majority of Australia’s sealed road network relies on the performance of unbound granular pavements with thin bituminous seal. Utilising locally available marginal materials is both economically and environmentally attractive to minimise transportation costs and reduce consumption of finite materials. In Queensland’s, regional and remote areas this presents considerable economic benefits. Marginal materials do not meet all the standard specification requirements for unbound pavement materials, however, when properly managed can provide satisfactory performance.
Identifying and classifying the fit-for-purpose material can be challenging depending on the extent of performance-based laboratory testing practically possible to replicate in-service conditions. The objective of this study is to investigate and rank the performance characteristics of marginal materials under a range of laboratory test conditions. The laboratory testing geotechnical characterisation and performance testing included wheel tracking, modified Texas triaxial, and California Bearing Ratio (CBR)
The study ranked the laboratory performance of a set of selected marginal materials from TMR regions in relation to standard conforming granular material. The outcomes of this study are expected to facilitate the development of a performance-based screening tool for marginal materials.
This paper discusses a part of the research study carried out for the National Asset Centre of Excellence (NACOE) project ‘P34’.
