Environmentally active GRC: towards better appearance of concrete and a reduction of air-pollution in urban environment

Following a brief review of the GRC as probably the most complex of construction materials, the focus is on a new, environmentally active glassfibre reinforced concrete: e-GRC. Introduction of the e-GRC represents a very significant and novel contribution to concrete practice, at a stage when the scientific and practical proof of the concept has been obtained but the technology has not yet reached the construction marketplace. Development of the e-GRC represents the third successful application of nanotechnology in GRC, unmatched in any other common construction material. It is based on a finding that a reduction in size of particles of a material down to nano-size often imparts new or enhances their existing properties. This is typical of nano-particles of titanium dioxide, which maintains its strong photocatalytic activity even when mixed with cement. External cement-based surfaces therefore become strongly photocatalytic, leading to a much better appearance through a 'de-soiling' effect together with a significant reduction in concentration of pollutants in the surrounding air. Traditional GRC is already mostly produced as thin-walled elements with large exposed surface and presents itself as an excellent material for practical exploitation of the photocatalysis. As only surfaces are active, the e-GRC also provides the most efficient use of the nano-sized titanium dioxide. The e-GRC therefore offers an economical and sustainable way to achieve long-lasting, cleaner and brighter concrete surfaces and a new way of achieving a significant reduction in pollution levels of surrounding urban environment. It provides architects with an additional tool to design and build genuinely 'greener' and better-looking concrete buildings. The e-GRC has a potential to improve the often poor general image of concrete, which tends to be associated with dirty buildings in polluted urban 'concrete jungles'. Benefits offered by the e-GRC indicate a more sustainable concrete construction with a direct and positive environmental impact is possible.