Beneficiation of recycled concrete fines through accelerated carbonation

A note on limitations of the use of accelerated concrete-carbonation tests for service-life predictions

Concrete carbonation is a process that can limit the lifetime of reinforced concrete structures. The resistance of concrete samples to carbonation is usually determined by accelerated tests under relatively high CO2-concentrations and a fixed relative humidity. No general agreement exists on whether and how the results of these experiments can be extrapolated to a natural setting. This note pre...

Reactivity in Recycled Concrete Aggregate

Full scale tests with crushed concrete used in sub-bases in roads show that the material has capacity to reharden, very slowly but also after prolonged periods of time. The rehardening process in crushed concrete aggregate has been analysed with a thermogravimetric method, comparing the change in chemical composition in the aggregate when set with water, compacted and hardened. It has been show...

Field Application of Accelerated Mineral Carbonation

Globally, coal-fired power plants are the largest industrial source of carbon dioxide (CO2). CO2 emissions from flue gas have potential for direct mineralization with electrostatic precipitator fly ash particles in the field. Demonstration scale accelerated mineral carbonation (AMC) studies were conducted at the Jim Bridger Power Plant, a large coal fired power plant located in Wyoming, USA. AM...

Assessing relationships among properties of demolished concrete, recycled aggregate and recycled aggregate concrete using regression analysis.

Recycled demolished concrete (DC) as recycled aggregate (RA) and recycled aggregate concrete (RAC) is generally suitable for most construction applications. Low-grade applications, including sub-base and roadwork, have been implemented in many countries; however, higher-grade activities are rarely considered. This paper examines relationships among DC characteristics, properties of their RA and...

Effects of Recycled Concrete Aggregates on Properties of Asphalt Concrete