Natural Fibre Reinforced Crack-resistant and spalling-controlled sustainable Geopolymer Concrete

ended

Shrinkage cracking and fire-induced concrete spalling can deteriorate the structural integrity and increase the maintenance cost of civil infrastructure. New advanced/sustainable construction materials can tackle these issues and also reduce the CO2 emissions which is an important factor in EU directives and codes of practice. The production of 1 tonne of cement requires 3-6 GJ of energy and releases approximately 0.85 tonnes of carbon dioxide, which, contributes to around 7% of the total man-made CO2 in the world. A significant amount of this CO2 can be saved by using environmentally friendly Fibre-Reinforced Concrete (FRC) made of recycled materials (such as geopolymers and recycled aggregates) and natural fibres (such as jute fibres). This proposal aims to develop: (1) an advanced understanding of the mechanisms behind the fibre-matrix compatibility in controlling cracking/spalling of concrete and (2) a novel, sustainable, cracking/spalling-controlled geopolymer natural FRC and a new technique which modifies the surface properties of natural fibres to enhance their bond with the cementitious matrix. This will enable the replacement of the currently used cement clinker and synthetic fibres with waste minerals and natural fibres, respectively, of equal or better performance, providing an annual reduction of 26 million tonnes of CO2 worldwide. The mechanisms of cracking/spalling of concrete, fibre-matrix compatibility and durability of jute FRGeo-Crete will be assessed by fibre pull-out tests along with the microstructural characterisation using SEM-EDS, FTIR, X-ray diffraction, and X-ray CT scanning. The lead beneficiary (The University of Sheffield - USFD) has world-leading expertise in the field of FRC design engineering and the use of waste by-products in concrete. The fellow will also receive an extensive training programme (delivered by the USFD), which will enable him to develop his career as an independent researcher.