Experimental Measurement of Volume Changes of Cement Concrete Specimens

AUTHOR(S):

TITLE

Experimental Measurement of Volume Changes of Cement Concrete Specimens

ABSTRACT

The paper describes experimental measurement of volume changes of cement concrete. Shrinkage is now becoming increasingly important with respect to concrete construction requirements, and it is important to be able to accurately measure and evaluate volume changes.Volume changes include swelling and shrinkage of cement concrete specimens. The experiment includes evaluating effects on volume changes and, depending on the environment, also evaluating individual types of volume changes in concrete such as drying shrinkage and thermal expansion. Volume changes was measured by string strain gauges both internal and external (with experimental casting method). The specimens were located in the laboratory and in the outdoor environment, so it was possible to compare values from different environments. Within the experiment, the measurement methodology of string strain gauges was unified for future experiments, which was one of the experiment goals. The measured results are compared with the calculation model of shrinkage (model B4). Comparison of shrinkage results with calculation models is important in designing concrete structures and developing other parameters for calculation models. The results from the experiment will serve to further investigate the volume changes depending on the subsoil. The concrete used in the experiment served as comparative, and the measured values would serve as a benchmark for dispersed reinforcement (steel fibers) concrete proposed in future experiments. Concretes with dispersed reinforcement using steel fibers has a positive effect on the reduction of volume changes and measurement of these concretes will be the next step of the research with the emphasis on building practice, especially industrial floors.

KEYWORDS

Concrete, Volume Changes, Shrinkage, Swelling, Model B4, Cement

REFERENCES

[1] AÏTCIN, Pierre-Claude. Binders for durable and sustainable concrete. New York: Taylor & Francis, 2008. ISBN 978–0–203–94048–8.

[2] AÏTCIN, Pierre-Claude a Sidney. MINDESS. Sustainability of concrete. New York: Spon Press, 2011. Modern concrete technology, 17. ISBN 978-0-203-85663-5.

[3] BAŽANT, Zdeněk. RILEM draft recommendation: TC-242-MDC multi-decade creep and shrinkage of concrete. Materials and Structures. 2015, 48(4), 753-770. DOI: 10.1617/s11527-014-0485-2. ISSN 1359-5997.

[4] ED. BY A. BENTUR. Early age cracking in cementitious systems: report of RILEM Technical Committee 181-EAS 'Early Age Shrinkage Induced Stresses and Cracking in Cementitious Systems'. Bagneux: RILEM Publ, 2003. ISBN 2912143330.

[5] KROPÁČEK, Michal a Jiří ŠAFRATA. Objemové změny cementů z různých lokalit v závislosti na čase. Sborník vědeckých prací Vysoké školy báňské – Technické univerzity Ostrava. Řada stavební. 2015, 15(1), 11-20. ISSN 1213-1962.

[6] HAVLÁSEK, Petr. Creep and Shrinkage of Concrete Subjected to Variable Environmental Conditions. Praha, 2014. Doctoral thesis. Czech technical university in Prague. Vedoucí práce Milan Jirásek.

[7] VINKLER, Marek a Jan L. VÍTEK. Drying shrinkage of concrete elements: Structural Concrete. Structural Concrete. 2017, 18(1), 92-103. DOI: 10.1002/suco.201500208. ISSN 14644177.

Cite this paper

Michal Kropacek, Radim Cajka. (2017) Experimental Measurement of Volume Changes of Cement Concrete Specimens. International Journal of Theoretical and Applied Mechanics, 2, 129-132