Mahdi is a Technical Director and the Net Zero National Structural Champion in Australia at WSP.
“My obsession with this topic led me to interrupt my consulting career and move to the academic world for few years to find innovative yet practical solutions for the material that has the highest carbon emission in our industry, i.e., concrete,” he says.
“The result of my research is contributing to shaping the next generation of standards and guidelines for low-carbon concretes. It also provides a basis for industry professionals and engineers to be able to specify these alternative concretes similar to traditional concrete.”
A well-respected WSP professional, Mahdi is a subject matter expert in achieving Net Zero in structural design. He holds a PhD from the University of New South Wales (UNSW) in low-carbon concretes and has more than 17 years of consulting and academic experience spanning a range of sectors including Residential, Commercial, Retail and Transport.
Mahdi’s research on low-embodied carbon concretes was recognised in 2019 with the National Award from Concrete Institute of Australia (CIA) and its outcomes was extensively used in developing TS 199 : “Design of geopolymer and alkali-activated binder concrete structures” that was recently published by Standards Australia.
Sustainable structural design solutions
There is currently no silver bullet to achieving Net Zero carbon emissions in structural design.
“The assumption of a sustainable structural design typically revolves around a simple substitution of the traditional materials such as General Purpose cement concrete with lower-embodied alternatives,” explains Mahdi. “While this is an efficient method of carbon reduction, it is only part of the solution.
“The commercially available low-carbon concretes provide an efficient carbon reduction, but still have a long way to go to achieve high percentage of reduction that gets us anywhere close to Net Zero targets.
“With the advancement of technology, in terms of both production of lower-embodied carbon materials and also grid decarbonisation, the material replacement approach will have a stronger role in future carbon reduction strategies. However, these incremental advancements could take years to mature and will not be quick enough considering the urgency of the climate change issue.
“In my view, we need to prioritise and promote responsible design approaches where material replacement is employed along with a range of other Future Ready™ measures, foremost among which, are preservation of the existing structures, design for circular economy principles, and design optimisation.”
Although preservation and refurbishment of existing buildings are the most efficient way of carbon reduction, it relies heavily on the condition assessment of the existing structure to develop a preservation strategy.
For this method to be effective, structural engineers need to be involved in the initial planning and concept design stages, working collaboratively with the asset owners, architects and other parties.
“Early involvement of structural engineers is key to success. It enables them to actively advise on reusing and recycling parts of the demolished structures, and developing a circular economy where the end-of-life cycle of materials play an important role in offsetting the upfront embodied carbon released during the early stages of the material production, delivery, and construction,” says Mahdi.
“Finally, design optimisation is probably the lowest hanging fruit among all the methods mentioned above in achieving the carbon reduction targets.”
“Published literature suggests that a 10 to 25 per cent reduction in carbon footprint can be achieved by design optimisation within the boundaries of the current building codes. Considering that Net Zero related topics are gaining momentum in both academia and industry, development of advanced optimisation methods that leverage state-of-the art technologies such as Machine Learning and Artificial Intelligence (AI) are certainly within our reach.”
Only the beginning
Although it is only the beginning of his journey towards Net Zero, Mahdi says this has been an exciting chapter of his career so far.
“It is a bridge between the business-as-usual structural engineering, research and development, and multi-disciplinary collaborative work on a subject that affects all of us in one way or another,” he concludes.
“Also, it is a great opportunity to play an active role in the industry, working with our clients to accelerate the paradigm shift that has already started in the Net Zero space.”
