This Paper reports an experimental investigation to establish the influence of ambient CO2, concentration, exposure temperature and curing duration on the rate of carbonation in concrete. The test specimens were concrete cylinders 100 mm in diameter and 200 mm high. Of the parameters investigated, the standard 28-day compressive strength f28 was found to be effectively representative of the concrete quality in several carbonation models proposed. Index test results, i.e. water absorption and sorptivity, were also incorporated to depict the effects of the surface property of concrete. The proposed models agreed well with the experimental data.
A closed-loop servo-controlled hydraulic testing machine can be used to generate experimentally the complete stress–strain curves for concrete in compression. However, the deformation readings obtained from the built-in low-voltage displacement transducers or other transducers placed between the machine platens include not only deformations of the concrete but also those due to machine flexibility and end-restraint of the specimen. In this paper, a correction factor is proposed to account for these effects. This requires the use of a compressometer fixed directly to the test specimen and transducers placed between the machine platens. More realistic stress–strain curves for concrete with cylinder (100 × 200mm) compressive strengths of up to 130 MPa have thus been obtained for the entire loading range.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.