by David Millar, CEO, Concrete Institute of Australia
Concrete is the most widely used construction material in the world, and the second most consumed substance globally behind water. In fact, the amount of concrete used worldwide is greater than the combined amount of timber, steel and other materials used to construct and build.
Dating back to early Egyptian times, humans have mixed together the basic ingredients of concrete from sand, gravel, cement-like binders and water for thousands of years. This was refined during Roman times where volcanic ash, or pozzolana, was used in concrete mixes due to its availability, and this reduced cracking and improved the durability of the finished product.
It’s no surprise that the product has endured as its properties lend itself to resistance against weathering, erosion, chemical attack, environmental exposure and natural occurrences, requiring very little maintenance.
Concrete’s continued popularity comes from the fact that it is not only economical but it is very strong and durable. When compared to other building materials, concrete has the capability to outlast them all significantly. It can even gain strength over time. Concrete is also an extremely versatile material and can be used to construct buildings, bridges, dams, tunnels, pavements, runways and roads. In fact, just about everywhere you look, you will find something built with concrete.
Rich history of concrete application
When you take a moment to analyse this, you can start to gauge the significant contribution concrete has made to society and the environment we live in. Australia, it should be noted, has led the world in many aspects of concrete and its application over the last 150 years, and continues to do so. Some of our achievements include:
Centrifugally spun concrete stormwater and sewer pipes, first manufactured in 1910 by Walter Hume, which have been patented and made around the world
The Gladesville Bridge in Sydney, when constructed in 1965, was then the world’s largest concrete arch span bridge
The Sydney Opera House saw a world record number of precast concrete panels being used in construction in the 1960s and 1970s
The first Gateway Bridge built in Brisbane, 1986, had the largest span, centre to centre to two piers in the world
The Burdekin Falls Dam in Ayr was the first modern gravity dam in the world constructed horizontally with conventional concrete
The Climate Change Institute at the University of Queensland in 2013 was the first use of geopolymer concrete for structural purposes
These, along with many other fabulous achievements in a rich history of concrete application in this country, are born on the back of a very solid understanding of the base material that in its simplest form consists of only four materials.
Yet it is an incredibly complex and interesting material. Despite the material having being around for hundreds of years, and providing many advantages to the built environment, it continues to be developed as new materials arise, and society and environmental changes need to be embraced. This is resulting in an unprecedented amount of research and investigation into new concrete materials, design and construction practices, and maintenance techniques and modelling, as the industry continues to strive to raise the bar.
A new breed of concrete technologists
However, with all these changes, something appears to be missing. In Australia today, there are a large number of stakeholders in this industry who contribute to research and knowledge development, as well as designing, producing and constructing concrete, with the objective of ‘getting it right’. Significantly, these stakeholders all understand the importance of concrete and the role it plays in engineering and society, but do they know enough about the base material?
At the recent Concrete Institute of Australia event, The Performance of Concrete – Materials & Specification, which focused on the materials we use for concrete in Australia today, this question was posed to me: Where have all the concrete experts gone?
Whilst this question is a vast generalisation – we have some of the best concrete materials technologists and practitioners in the world – it is fair to say that there isn’t a big line of people waiting to take over when our experts in this area retire and move on to other things. Why is this?
There is a changing landscape in engineering and construction in Australia today. Concrete as a material is feeling this impact as the major stakeholders in the industry are all moving with the times. So why isn’t there a new breed of concrete technologists knocking the door down?
Is it because of changes in engineering courses? With such a focus on innovation and new materials, universities are turning their attention more and more to research activities. There is also a trend that sees curriculum being set that appeals to a broader base of potential students to remain competitive and modern. As such, some courses have reduced their concrete materials content considerably, attempting to cover the complexities of the material in a short period of time (if at all).
Once upon a time, materials engineering and science was a significant part of a civil engineering students load. As a result, there was a good understanding of basic concrete materials fundamentals, and if desired, students could further the knowledge in specific areas as they advanced. Due to many changes in the way university courses are structured today, have the opportunities for more detailed and thorough learning of materials technology waned?
Is it because of changes in the construction industry? Is everyone so conscious of delivering projects on time, and under so much pressure to deliver, that having concrete materials experts as part of the everyday team to ensure that the right design, specification and supervision, is not seen as being viable to the overall efficiency?
Designers and specifiers are under pressure to deliver outcomes for consulting groups in an ever increasing competitive space. This is further emphasised by the influx of large global organisations that are positioning themselves in Australia, and their need for accountability and performance. Is there enough attention being placed on understanding concrete essentials?
Suppliers are under pressure to meet growing demands for a product that must be available at a moment’s notice, meet numerous specification requirements, adapt to changing conditions and trends, yet must remain economical. Along with concerns with ongoing natural resource availability, this could be having an impact on the quality of our raw materials and finished products.
The knowledge gap experienced at government level (local and state) has been identified for some time now. This has led to a change in specification philosophy at many organisations with an emphasis on reducing the risk in concrete design, production and placement due to diminishing resources and experience.
The construction sector continues to move at a rapid rate of knots, and as they look to maximise efficiencies and effort, ensuring that projects are completed on time and within specification, is there enough time and experience being devoted to ensure that the concrete being used is of the quality required for the structure?
Is it because of changes in the way we continue to learn? Not that long ago after leaving university, if you needed specific training or revision of aspects of concrete materials, design and construction you were straight off to a one or two day course to get up to speed. Or, you were off to a precast yard or ready mix concrete plant to learn the basics. Bookshelves had copies of A.M. Neville’s Properties of Concrete for reference. These days professional development requirements at organisations, along with training and education platforms, have changed. Is the knowledge required in concrete materials able to be transferred via modern learning methods?
Getting back to basics
The real question that should be asked from all of this is, with all this pressure to compete, perform and act efficiently, is it having an impact on our knowledge, design and application of concrete construction in Australia?
Michael van Koeverden from CQT Service, and Immediate Past President of the Concrete Institute of Australia, recently said, “While advances have been made in admixtures, binder and aggregate production, fitments, testing and repair materials, the root cause behind many of our concrete problems is neglect of the basics.
“All areas of the concrete industry need to have an understanding of concrete the material and how it works. Designers must consider whether their designs can be built. Constructors must ensure they allow for realistic construction time frames with experienced supervision part of the process. Placing, compaction and curing of concrete must be undertaken correctly for all concrete construction. You only get one chance to ‘get it right’ with concrete, so asking the right questions at the right time is essential to getting the right outcome.”
These innovations, and many others, demand that the industry be focused, knowledgeable and willing to take a chance in challenging established products and procedures. It also means that we must be armed with the essential knowledge of a material that may look simple but can be incredibly complex.
The concrete construction industry in Australia has a history that is based on hard work and sound knowledge. As we continue to use more and more of the world’s most used construction material, in today’s changing landscape, more than ever we must ensure that everyone has the basic knowledge of this complex material called concrete.
It is with a small slice of irony that in Melbourne in October the Concrete Institute of Australia will play host to the largest gathering of international concrete experts ever seen in this country at the International Federation of Structural Concrete (fib) Congress 2018. At the time of writing, there were over 400 delegates from over 40 countries registered to attend with over 700 people expected by the time the congress commences. There may never be a better opportunity in this country to ‘start knocking on the door’ and get back to basics.