The way forward …
We have been using concrete in one form or another for several thousand years. In the last one hundred years or so, concrete has driven the growth of the world’s cities and national infrastructure.
But … what of the future? While there are some alternatives to the use of concrete, it would appear that concrete will continue to be the construction material of choice for some time.
Of course, concrete will no doubt adapt as technology moves on and will respond to changes in social and environmental requirements. In this blog we take a look at some of these new advances.
- Green Concrete:
As environmental concerns grow, there is increasing interest in developing “green” concrete, which has a lower carbon footprint compared to traditional concrete. It has been estimated that the production of concrete’s key component, Portland cement, accounts for between 5% and 8% of global CO2 emissions.
Energy hungry cement production
Using alternative materials, like fly ash, slag, or even industrial byproducts, to reduce the amount of Portland cement required enables a greener concrete to be produced.
Alternative mixes can be used to produce concrete with different properties, increasing its suitability for a variety of applications. Apart from the obvious advantage of reducing CO2 emissions, government and local authorities may start to offer tax incentives for using greener concrete (as well as mandating its use) in construction projects.
- High Performance Concrete:
Engineers and researchers are continuously working on developing concrete mixes with enhanced properties, such as higher strength, durability, and resistance to environmental factors like corrosion and abrasion.
These improvements can lead to longer lasting and more reliable structures. Standard concrete is considered to offer 5,000 psi whereas high performance concrete is expected to deliver strengths of around 12,000 psi.
This achieved by using supplementary cementitious materials, reactive powders, limestone and or quartz flour, fine sand and water reducers.
Ultra-high-performance concrete has a minimum compressive strength of 17,00 to 21,000 psi. Typically fibers are introduced to the mix along with the fine materials to achieve this level of strength.
- Self Healing Concrete
Researchers are exploring the incorporation of materials that allow concrete to “self-heal” cracks that may form over time.
These materials could react with water and atmospheric carbon dioxide to form mineral deposits that fill in small cracks, potentially extending the lifespan of structures and reducing maintenance needs.
The concrete used by the ancient Romans has been found to be “self healing”; this is a result of the composition of their mortar producing a process which has been found to continue over 2,000 years.
The Pantheon, Rome – still standing since AD 125
Production of standard products with this self-healing property is still in the research phase but clearly offer potential benefits to construction.
- 3D Printing
3D printing technology is being adapted to construct complex concrete structures with greater efficiency and reduced material waste.
This could revolutionize the construction industry by enabling the creation of custom-designed buildings and components.
Results of resilience measurements suggest that a balanced 3D printed concrete house could last for about 50–300 years.
- Nanothechnology
Nanomaterials can be added to concrete to enhance its properties.
For instance, nanoparticles can improve the material’s strength, durability, and resistance to various environmental factors. They can also help mitigate problems like cracking and increase the overall lifespan of structures.
While still the subject of on-going research the addition of graphene oxide has been shown to provide strength gains of around 30% with reduced permeability.
The molecular web of graphene oxide
While nanomaterials such as graphene oxide do carry extra cost, only tiny quantities are needed … 0.05% of the mix … a few grams per batch.
- Smart Concrete
Incorporating sensors and other technology into concrete can provide real-time data on factors like stress, strain, temperature, and humidity.
This “smart” concrete can help monitor the health and integrity of structures, enabling timely maintenance and reducing the risk of failure.
The sensors used can also measure the “maturity” of the concrete, i.e. how it is curing and developing its strength.
Hilti sensors
Using concrete sensors such as provided by Hilti also enables monitoring of the temperature of the concrete … https://concretesensors.com/
- Recycled Aggregates
Using recycled materials as aggregates in concrete production can reduce the demand for virgin resources and decrease waste.
This approach aligns with sustainability goals and reduces the environmental impact of construction.
Recycling of concrete is a relatively simple process involving breaking, removing, and crushing existing concrete into a material with a specified size and quality.
Mobile crusher recycling reclaimed concrete
The quality of concrete with RCA is very dependent on the quality of the recycled material used.
Rebar and other embedded items must be removed, and care must be taken to prevent contamination by other troublesome materials such as asphalt, soil and clay, glass, gypsum board, plaster, wood and roofing materials.
It is generally accepted that when natural sand is used, up to 30 percent of natural crushed coarse aggregate can be replaced with coarse recycled aggregate without significantly affecting any of the mechanical properties of the concrete.
In conclusion, the future of concrete in construction will likely be characterized by increased sustainability, advanced materials, digital integration, and innovative construction methods.
These trends aim to address the challenges of resource scarcity, environmental impact, increasing construction efficiency, reducing costs and the need for more resilient and efficient structures.