For nearly four years, Tharanga Ranasinghe from the University of Adelaide has made rolling dynamic compaction (RDC) the focus of an extensive research project she has undertaken while studying for her PhD in civil engineering.
“RDC is a process that has proved to be effective for mine site compaction, pavement construction and earthworks. In pavement construction RDC can help achieve a more uniform subgrade from the ground surface without excavating material,” says Mrs. Ranasinghe. “It can also be used for proof rolling because it can isolate soft spots in the ground.”
Mrs. Ranasinghe’s research is focused on transport infrastructure and road construction, with a specific emphasis on the impact of the square-shaped module conventionally used in RDC.
“The square shape can improve the ground to depths in excess of three metres in some soils. Traditional rollers typically can’t compact to that level.”
A square module, attached to the back of a tractor, can move at up to 12 kilometres per hour, compared with the traditional roller, which can reach about four kilometres per hour.
“While this method is used widely, there is no exact means of predicting its effect – there is no model to estimate the impact of this kind of roller,” explains Mrs. Ranasinghe.
Before RDC is used on a project it needs to be trialled on site. “It can be costly and time consuming, but that’s how estimates are made for the time being,” she says.
Nearly four years since starting her research, Mrs. Ranasinghe has developed a numerical model that may have significant implications for RDC use on civil projects.
Mrs. Ranasinghe’s model can help contractors determine the number of passes required for the RDC square module roller to effectively compact the area.
“Focusing my model towards the four-sided impact roller, I used all the data from square-shaped rollers used on projects from Broons Hire.”
The data she assembled from Broons includes soil type, density, load type and other variables that have been acquired over more than 30 years of projects. By combining that information with artificial intelligence technology, the model can ‘learn’ from previous experiences and estimate how many passes are required, based on the site’s characteristics.
“By using my model, a contractor can see the variables they need to consider and predict and plan ahead,” she states.
Mrs. Ranasinghe says the model helps to make the RDC method a more viable option, and has subsequently been recognised by industry and her peers.
Mrs. Ranasinghe is one of four regional prize winners in the 2016 ARRB Student Transport Research Prize Scheme, presented by ARRB and Roads Australia.
Students studying science, technology, engineering and mathematics (STEM) subjects at universities across Australia and New Zealand are awarded a share in $15,000 under the prize scheme for presenting the most forward-thinking ideas for roads and infrastructure research projects.
As part of the award submission, students were required to draft an elevator pitch to a road agency chief executive, with the aim of attracting interest in the research findings and demonstrating how they could assist the agency in achieving its goals for the road network.
The regional winners are now eligible for the peak Australasian prize, which is worth an additional $2,500.
She says Broons were quite open-minded and happy to take part in the project.
“The data comes from Broons Hire field trials and over 30 years they have done more than 1000 large civil projects all over the world. Through this collaboration they have allowed me to access their impact rolling database, and we came up with a numerical model from that,” she says.
Mrs. Ranasinghe says the recognition through the ARRB Student Transport Research Prize Scheme has been a great honour, and is a good example of the benefits of entering into the civil engineering sector.
“Civil engineering is really interesting because there’s always something new to design and be involved in,” she says. “It’s going to be an interesting industry for the next generation, and I would encourage them to give civil engineering a go.”
Mrs. Ranasinghe wanted to thank her supervisory panel: Prof. Mark Jaksa and Drs. Yien Lik Kuo and Fereydoon Pooya Nejad from the University of Adelaide; Stuart Bowes from Broons Hire; Brendan Scott from the University of Adelaide; and her main funding source – Australian Research Council’s Discovery Projects funding scheme.
Her work demonstrates the milestones that can be achieved in innovation through a collaborative approach between industry and research institutes.
Mike Shackleton, Executive Manager of ARRB Academy, is adamant this relationship between researchers and industry is critical for innovation to flourish within the nation’s transport and infrastructure sector.
“We at ARRB see it as being absolutely essential because it makes for more systematic development of successful innovations from research. We look at research ‘success’ from an innovation point of view as public and private sector funders of research assess their return on investment that way,” asserts Dr. Shackleton.
He explains that innovation in itself emerges through collaboration between public, research and private sectors. The public, for instance, has to be included in the discussion as they are the end users, for whom the innovation is ultimately implemented.
“The research sector provides scientific rigour to make sure that whatever comes out of the process is robust and reliable,” adds Dr. Shackleton.
Thirdly, he says the private sector is crucial to this formula, as it is the component that drives efficiency in the implementation of research-based innovation.
He says that the relationship between researchers, such as Mrs. Ranasinghe, and companies, such as Broons, are essential cogs in the mechanics of innovation, and exemplify just how far this relationship has come in the past couple of decades.
This harmony was not so well established 20 years ago. “I think researchers have seen their relationship with industry as an important one, but they weren’t good at communicating how their research could or should have been applied. Ironically, they weren’t happy when no one would take up their research,” he says.
These days, however, he says researchers are becoming better at communicating, and the relationship with industry partners emerges naturally.
“Universities are now appointing deans and head of departments who are very focused on research collaborations with industry. They need that partnership for both financial reasons and to make sure the research the university does is relevant and is actually used out there,” he adds.
“What we do differently at ARRB is that we emphasise to our staff, and to trainee researchers like Tharanga, that the best research in the world isn’t worth much unless it’s well communicated.”
In turn, industry has recognised the value of the relationship with researchers too. “Research and development doesn’t always go where we think it’s going to go, and for smaller companies that can mean a lot of lost revenue and costs,” explains Dr. Shackleton. “They’ve realised the value that trained researchers and universities bring as part of managing research and development risk and that’s something they hadn’t seen a few decades ago.”
While the relationship between researchers and industry has come a long way, Dr. Shackleton explains there is still room to become more systematic in forming them, particularly as game-changing technology begins to emerge.
“Any time we’re moving onto another level of uncertainty, the more people we have working together on the problem, the better chance we have of implementing that technology optimally,” he says.
Driverless technology, for instance, is a complicated concept in the context of road regulation, safety and implementation, as it involves a massive cross-platform of stakeholders with different views and perspectives and a wide range of technical disciplines. “You have one shot at getting it right, and there’s better chance of achieving that when working with a range of people who have different views,” he says.
He further asserts that the relationship between researchers and industry is critical to continued innovation and the development of the next generation of researchers and engineers.
“The next generation of researchers will be drawn from the millennial cohort.”
Dr. Shackleton believes that with their strong sense of community and desire to make a difference, they are ideal participants in collaborative research partnerships between public, private and research sectors, which lead to positive change. “On top of that they are natural knowledge workers as they are being completely at home with seeking out knowledge and reconciling several sources of it,” he says. “If we nurture this generation, we will be rewarded with problem-solvers who thrive in the circumstances which lead to innovation and change, where previous generations had to learn – often slowly.”
ARRB sees that the industry’s task will be to keep these researchers engaged in the transport sector’s challenges. While the accelerating pace of change ensures that there will be no shortage of problems to solve, he says the industry needs to be working as one to ensure that they are given opportunities to address them from more than just the researcher’s perspective, through industry-wide rotation or exchange programs. “At ARRB, we would love to see this happening and would regard it as a collective win for the road and transportation sectors.”