Imagine a modern high-rise building with no steel. Sound implausible? Not any longer, thanks to carbon nanotube technology (CNT). While cost is still a major factor, the technology now exists to develop very high strength, ultra-low permeability concrete that requires little or possibly no steel reinforcing.
Eden Energy, an Australian listed company, has worked with Monash University to develop a suitable CNT-enriched liquid mixture that Eden will manufacture, which can be added to concrete to make it tougher and stronger. Eden will commence its first US commercial trial of CNT-enriched concrete during late 2014, and start Australian trials in 2015 with a major global concrete company to test a range of applications.
Some anticipated benefits of CNT-enriched concrete include tougher, more abrasion-resistant concrete for roading, bridges, airport runways, warehouse floors, car parks and other heavy usage areas. It would be especially suited to areas where the concrete surface is exposed to abrasive cleaning, such as the use of snow ploughs, which produces excessive wear and high maintenance costs. Because these applications generally do not require much, if any, flexural strength, this is likely to be the initial market for the new concrete. It will require testing only of the compressive strength, and it is hoped that a commercial product could be available late in 2015 or early in 2016 when the initial trials are completed.High-rise applications
Stronger concrete suitable for high-rise buildings that requires less concrete and steel reinforcing (or perhaps even none) could produce lighter, stronger structures with smaller footings, thinner slabs and narrower columns.
Significantly denser, far less permeable concrete, due to the increased density of the cement gel, would greatly reduce the gradual absorption of saline water, making it highly suited to a wide range of harsh marine and coastal applications, especially if steel reinforcing is not required. The stronger, lighter and less permeable concrete would also be well suited for use in dam walls and spillways, and water and sewer pipes for large-scale infrastructure projects.