An international team of scientists and infrastructure experts are seeking to understand the drivers of unsealed road damage and riverbank erosion to help local councils provide more resilient and sustainable roads.
James Cook University civil engineering researcher Dr Liuxin Chen and her colleagues have received an Australian Research Council Discovery Grant to work with councils and road construction experts on improving unsealed road corrugations, aiming to minimise repair costs and promote more sustainability in construction and road maintenance solutions.
"To improve resilience, we need to know the exact reasons for road failures such as corrugations and rutting, so we can develop new strategies to deal with them," Dr Chen explained.
"The current approach to managing damage to our roads and rivers from climate extremes such as heavy rainfall are ad-hoc and reactive … mostly because we still don't know the mechanisms underpinning how or why this damage occurs."
Dr Chen and academics from Monash University and University of Illinois Urbana-Champaign will undertake the three-year research project involving two PhD students and a postdoctoral research fellow working together on the complex challenges.
"This project includes developing a corrugation simulator to understand the effects of water and vehicle stresses, and advanced modelling so we can predict how extreme rainfall will impact on construction practices and the durability of road materials," said Dr Chen.
Unsealed roads represent 63 per cent of the Australia's national road network, serving a vital role for regional and remote communities as well as economic activities such as tourism, mining and agriculture.
Roadside damage such as corrugations and rutting compromises safety, hinders public access, increases vehicle operating costs, and places large financial burdens on local councils and governments.
Increasingly intense rainfall events associated with a warming climate and heavy wet seasons are set to make unsealed road and riverbank damage worsen further.
"One of the most important drivers of road failures is soil moisture. If we got lots of water inside the soil, the soil becomes fully saturated, and we get lots of problems," Dr Chen said
"Here in Queensland, the Mt Spec Road to Paluma was severely damaged after extreme rainfall. If we rebuild that road back the same way, we can expect to see exactly the same problems happening again and again."
In parallel with her work on unsealed roads, Dr Chen has secured funding to collaborate with several north Queensland River Improvement Trust organisations to study riverbank stability and riverbank erosion.
"We will be focussing on the performance of existing riverbank works, such as timber pile systems, which have been widely implemented but not yet been systematically assessed," she said.
"These projects are about building a stronger evidence base for sustainable, resilient geo-infrastructure.
"By understanding how soils behave under real operating conditions and working closely with those responsible for managing assets, we can support safer, more reliable, and more sustainable outcomes for Australian communities."
