果冻影院

By understanding and changing how crystals form in cement, scientists are finding ways to reduce the impact of concrete on the environment.

Cement forms the basis of concrete听鈥撎齮he single most widely used material in the world.听听

鈥淢anufacture of cement听worldwide accounts for听approximately听eight听per cent听of听all听human-produced听carbon dioxide,鈥� explains Professor Ian Robinson听(果冻影院 Centre for Nanotechnology).听

Professor Robinson鈥檚听research听aims听to听adjust the听composition听of听cement so it can act as a carbon sink and听offset听some of the听carbon dioxide听produced during its manufacture.听听

However,听the complexity of听cement manufacture and听the听way听critical components of cement react听with each other, affect how the concrete performs.听If听chemical reactions within the cement are听suboptimal,听the听concrete听weakens, which can end in听disaster.听For example,听adulterated cement听contributed to听the听widespread听collapse of听buildings听during听an听earthquake in Izmit, Turkey,听in 1999,听which听killed听17,000 people.听

鈥�This would听partially replace cement clinker听鈥� an important component of cement manufacture produced at听high temperature in a kiln 鈥撎齭aving听energy and reducing听CO2听emissions听

Professor Robinson鈥檚 team is using X-ray imaging methods, developed using the UK鈥檚 Synchrotron, to understand the performance of cement and concrete materials, working in collaboration with the听School of Materials Science and Engineering,听Tongji University, Shanghai.听

鈥淥ne听of our goals is to make small听changes听in听cement鈥檚听composition, without spoiling听its听performance,鈥� he explains. 鈥淔or example,听by听adding听appropriate听amounts of听industry by-products such as听fly ash听and granulated blast furnace slag.听

This would听partially replace cement clinker听鈥� an important component of cement manufacture produced at听high temperature in a kiln 鈥撎齭aving听energy and reducing听CO2 emissions during cement production, as well as听reducing听the听impact on the听environment for the life of the cement.听

鈥淲e are听looking听at听calcite听鈥撎齛 compound that听forms听during听cement听hydration and听can act听as a carbon sink,鈥澨齈rofessor Robinson explains.听

Using听X-ray imaging,听the team is听closely examining听calcite nanocrystal听growth听in听high and low听CO2听conditions听to听check for irregularities and defects in the crystal structure that could affect听the concrete鈥檚听performance.听听