Advanced Materials

Construction materials are used in many different situations and as a result have to cope with many different environmental conditions, as well as fulfilling their primary role of strength and support. The properties of materials can often be enhanced through combination, e.g. steel reinforced concrete is stronger and more resistant to deformation stresses than concrete alone. However, such reinforced concrete is at the mercy of the elements. Repeated hot and cold, and wet and dry cycles eventually cause the concrete to crumble, exposing the steel which then corrodes.

New composite materials based on advances in nanotechnology can address these problems. The addition of nanotubes and ceramic nanoparticles to materials such as concrete and polymers can increase their load-bearing abilities, increase their resistance to environmental conditions (such as extremes of hot and cold, or corrosive salt conditions, or immersion in water), and increase their ability to cope with other stresses such as collision or movement (e.g. earthquakes) without shearing or breaking. These advantages are realised through improved binding of the bulk material (e.g. concrete or polymer) leading to a highly ordered, internal nanostructuring of the composite. This replaces the need for heavy support materials (such as steel) and also eliminates the possibility of future weakening due to corrosion.

New composites can also enhance the thermal insulation properties of construction materials (see the insulation section in Energy), as well as improving fire retardancy. In this respect there is a lot of interest in using nanomaterials in combination with wood (which is still a major construction material for housing).

Not only are such materials stronger and more durable than traditional ones, they are also lighter. This means that construction using such components is quicker and does not require heavy lifting machinery. Already several bridges around the world have been repaired or constructed using composite materials based on microtechnology. Nanotechnology enabled adavances are expected to further improve on the mechanical properties of such composites.