Concrete is one of the most widely used construction materials in the world. It’s durable, cost effective and environmentally friendly. But how can we improve its performance to tackle today’s challenges?
Fortunately, several innovations have emerged to enhance concretes’ capabilities. Here are 6 of the latest innovations to watch for in 2020.
Self-Consolidating Concrete (SCC)
SCC is an advanced concrete that can be used in a variety of construction applications. It has the ability to flow under its own weight to fill forms or encapsulate dense reinforcement. It does not require the use of vibration or other techniques to consolidate the concrete, which saves time, labor, and equipment costs. This concrete also provides the flexibility to create a wide range of aesthetic finishes and shapes that would be difficult or impossible with conventional concrete.
Conventional concrete is a thick and viscous material that must be compacted with mechanical vibration in order to achieve proper placement. This can lead to undetected imperfections in the concrete such as honeycombing, cavitation or other gaps that weaken the structure over time. SCC can be placed without compaction, reducing equipment and labor costs as well as improving the quality of the concrete.
The SCC process uses a combination of mineral admixtures and high water-reducing cements to create this unique concrete. SCC mixes are designed to have a low slump flow and a high level of plasticity, which allows them to easily encapsulate dense formwork, or place concrete in difficult areas such as tunnel linings, tubing segments or drill shaft columns with a high rebar concentration. This type of concrete also allows for a higher rate of production and allows the concrete to be pumped long distances, which improves turn-around times on concrete trucks.
SCC is able to achieve these high levels of fluidity and plasticity through the use of highly advanced high-range water-reducing admixtures and viscosity-enhancing admixtures. This allows the concrete to be poured at lower slump flows, which can be reduced even further by using a lower water content in the mix. This helps to ensure the concrete will reach its intended jobsite in good condition, with minimal bleeding and segregation.
The PCI SCC Guidelines are currently being circulated to all precast/prestressed producers and their design engineers. This document will help to guide these important industry stakeholders on the appropriate ways to utilize this innovative product. The benefits of SCC will ultimately benefit all involved: savings in production labor, longer form life, fewer bug holes, reduced patching and an improved work environment that is free of vibration.
Artificial Intelligence (AI) Powered Operating System
Construction projects face numerous risks that may jeopardize safety, quality or time. These risks are magnified in large projects with multiple teams and subcontractors. A unified platform that can assess and monitor data such as equipment, weather patterns, downtime and other factors helps project managers avoid costly overruns. Ultimately, project stakeholders benefit from an AI-powered operating system that combines all the components of a project into a single software interface.
Consolidating the planning and oversight of construction’s many moving parts into a single software platform provides project managers with an unprecedented level of transparency and efficiency. This platform will not only help project teams manage risk, but it will also reduce costs and speed up the process of bringing onboard new workers.
The key to promoting the converged innovation of AI is to build and improve specialized public maker spaces in the AI field, based on colleges and universities and scientific research institutes concentrated in localities. Encourage leading and backbone enterprises to take the lead in establishing marketized AI development bases, and enhance their role in building a national AI mass innovation base. Develop innovative application demonstrations, and strengthen the interactive evolution of technology breakthroughs, domain applications, and industrial development.
Moreover, support the establishment of international AI science and technology cooperation bases, joint research centres, and related international standards. Encourage domestic advantageous enterprises, industry alliances, and academic institutions to jointly establish AI public patent pools.
The future of AI in engineering and construction (E&C) is a promising one, with the potential to dramatically streamline processes and eliminate manual tasks. Its adoption will also help to improve project quality, increase safety on the jobsite, and reduce costly errors. However, the full benefits of AI in E&C will only be realized if companies can overcome barriers and implement the technology. In doing so, leaders should focus on specific areas where AI can have a direct impact on their business, and embrace the spirit of “hammering nails” in order to accelerate implementation with a pragmatic mindset. The early movers will set the direction and reap both short- and long-term benefits.
Self-Healing Concrete
Concrete is one of the most popular building materials in the world. Its versatility and affordability make it a great choice for building infrastructure that will last centuries. However, it is not without its problems, including the potential for cracking and leaks. Every year billions of pounds are spent maintaining and repairing concrete structures. Fortunately, these problems may be a thing of the past as new technologies emerge that improve concretes ability to heal itself.
Researchers at Worcester Polytechnic Institute (WPI) have developed a self-healing concrete that is four times more durable than conventional concrete. The new material consists of calcium carbonate crystals that are able to fill and close small cracks in the structure. This makes the concrete more resistant to damage and extends its lifespan significantly.
The secret to WPI’s self-healing concrete is the presence of an enzyme that automatically reacts with atmospheric carbon dioxide to create the calcium carbonate crystals. This reaction is triggered by the hydration of the cement particles and results in the formation of new crystals that close the cracks.
While it is not yet possible to produce self-healing concrete that can repair very wide cracks, this type of product is a significant step in the right direction. The WPI’s breakthrough could mean significant cost savings for a wide range of building projects that require the use of concrete.
Another approach to developing self-healing concrete is based on microorganisms. In this case, the concrete is mixed with bacteria that can seal cracks when water penetrates the structure. Hendrik Jonkers, a microbiologist at Delft University, has been working on this technology for over three years and has successfully tested the concrete in his lab.
The bacteria used in the concrete is a strain of bacillus that thrives in alkaline conditions found in concrete. During mixing, the bacteria remain dormant, only activating when they are exposed to water in the form of cracks. The bacterium then forms limestone, closing the crack and preventing further deterioration of the concrete. This technique can be applied to both new and existing structures.
CarbonCure
Concrete is a major contributor to carbon emissions due to the large amount of portland cement used. As more building owners seek to reduce their embodied carbon footprint, CarbonCure offers an alternative solution that is said to significantly cut the carbon footprint of concrete without impacting its strength and durability.
The Halifax, Nova Scotia-based company’s technology is retrofitted into existing concrete plants and injects a precise dose of captured CO2 during the mixing process. The CO2 mineralizes into calcium carbonate that is permanently embedded in the concrete. This process is said to improve the concrete’s early and late-compressive strengths, enabling concrete producers to optimize their mix designs while reducing their environmental impact and generating market differentiation.
As of this writing, CarbonCure is used by nearly 250 concrete producers in North America and Southeast Asia. The largest structure built with CarbonCure concrete is the Kendeda Building for Innovative Sustainable Design at Georgia Tech in Atlanta, which was poured with CarbonCure-treated concrete in 2017. Ready-mix producer Thomas Concrete has also been a major customer of CarbonCure’s technology since 2016.
With more companies focused on net-zero carbon plans and other sustainability initiatives, it is expected that the use of concrete made with CarbonCure will continue to increase. In fact, the company recently closed a funding round led by Breakthrough Energy Ventures, and its chief executive says another could follow soon.
Wagner declined to share revenue figures, but the company has been growing at more than 100% per year for several years and is now generating annual sales in excess of $10 million. It is currently targeting European markets, where building standards are more strict.
The company’s technology has been independently verified as carbon negative by Verra, making it the first and only permanent concrete-based carbon removal solution to receive this distinction. The Verified Carbon Standard program requires technically sound GHG-reduction quantification methodologies specific to the concrete industry, along with comprehensive documentation and life-cycle assessments.
In addition to helping to reduce a concrete’s carbon footprint, CarbonCure’s technology is also said to create production cost efficiencies and eliminate plant water and solid waste. Further, extensive testing with a wide range of admixtures has shown that CarbonCure does not negatively affect the performance of concrete, and it can be used in combination with any supplementary cementitious material.