Features of Expanded Clay Foam Concrete Hardening Regimes in Natural Conditions and Warming

https://doi.org/10.35579/2076-6033-2019-11-12

ABSTRACT

Еxpanded clay foam concrete is a conglomerate material produced using expanded clay gravel. as a binder foam concrete mixture and filler. The article presents the results of experimental research and provides the justification for the various modes of hardening of the foam concrete - binder, and expanded clay foam concrete, providing them with the required physical-mechanical and thermal properties. Using standardized and variable (author’s) techniques, the patterns of kinetics of growth of expanded clay foam concrete strength in different temperature conditions in the range of the temperature of the environment from 0 ^oC to 20 ^oC (with “natural” firmness) and warming up, with temperature increasing up to (60... 80) ^oC were investigated.

The regularities of “self-warming” of solid expanded clay foam concrete are due to the accumulation of heat exothermy of cement as a factor contributing to the increase of the growth rate of expanded clay foam concrete in “natural” hardening and in the conditions of warming are applied to both monolithic construction and prefabricated products.

The results are important in fact of the lack of verified and unequivocally recommended hardening modes for the foam concrete (and especially expanded clay foam concrete) in monolithic construction in both regulatory and technical literature. Current standards for the use of foam concrete provide general recommendations for works in the warm period of the year (i.e. - seasonally, at a positive temperature of invironment), intended and related to specific conditions of works. To develop various hardening modes, expanded clay foam concrete tests were carried out on samples (sizes 600 x 1200 x 2400 mm) made in forms of laminated moisture-resistant plywood (z 20 mm), simulating a formwork variant (for monolithic construction), and the form for the factory manufacturing of piece goods. The studies used an averaged (medium density criterion from the D300 range... D800) composition of the D500 expanded clay foam concrete with the optimal consumption of expanded clay gravel 0.8 m³ in m³ of concrete. The article contains the results of the experimental justification of the recommended hardening regimes of expanded clay foam concrete in conditions of “natural” hardening and using the thermal treatment.

Keywords: foam concrete, expanded clay foam concrete, firming conditions, firmness mode, hardening kinetics, strength, properties.

For citation: Mordzich M. Features of Expanded Clay Foam Concrete Hardening Regimes in Natural Conditions and Warming. Contemporary Issues of Concrete and Reinforced Concrete: Collected Research Papers. Minsk. Institute BelNIIS. Vol. 11. 2019. pp. 189–204. (in Russian)

Full text in Russian:



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