Study into the freeze-thaw/ frost-salt resistance of high-strength B60–B100 concrete

Introduction. The development of the Arctic Region and oil and gas fields in the North Atlantic Ocean leads to an increase in the production of high-strength concrete structures. Thus, it is becoming increasingly vital to make such low-permeability concretes more freeze-thaw resistant.

Aim. To conduct experimental studies for obtaining reliable data required to develop a standardized approach to the normalization of freeze-thaw / frost-salt resistance parameters characterizing high-strength concretes.

Materials and methods. The study was performed using concretes of eight compositions (B60–B100 compressive strength grades). The freeze-thaw/frost-salt resistance of high-strength concretes was determined using the third rapid method involving the saturation, freezing, and thawing of samples in a 5 % sodium chloride solution, as well as assessment of freeze-thaw resistance in terms of strength, mass variation, and the dynamic modulus of elasticity. A variety of methods for increasing the water saturation of highstrength concrete were examined in order to expedite the testing process of high-strength concrete for freeze-thaw resistance.

Results. The studies into the freeze-thaw/frost-salt resistance of high-strength B60-B100 concretes revealed their high freeze-thaw resistance. Following 37 freeze-thaw cycles, the lower confidence limit for the strength of test samples was higher than that of control samples multiplied by a coefficient of 0.9. The frost-resistance grade of these concretes is above F2 300. No critical decrease in the dynamic modulus of elasticity is observed, which indicates a significant freeze-thaw/frost-salt resistance of all tested highstrength concrete compositions.

Conclusions. The freeze-thaw resistance studies of high-strength concretes carried out at NIIZHB named after A.A. Gvozdev yielded experimental data required to subsequently develop a standardized approach to the normalization of freeze-thaw/frost-salt resistance parameters characterizing high-strength concretes.

1. GOST 10060-2012 Concrete. Methods for determining frost resistance. Moscow: Standartinform Publ.; 2012. (in Russian).

2. To conduct research on frost resistance/frost and salt resistance of high-strength concrete of class B60-B100 for structures of buildings and structures for various purposes intended for operation in permafrost conditions. R&D report. State registration N NIOKTR 121061600030-2. Moscow: NIIZHB; 2021. (in Russian).

3. Stepanova V.F., Chekhniy G.V., Parshina I.M., Orekhov S.A. Study of the frost resistance of concrete in order to adjust GOST 10060-2012. Vestnik NIC Stroitelʹstvo = Bulletin of Science and Research Center of Construction. 2021;30(3):78–87 (i n Russian).

4. Sheinfeld A.V. Scientific bases of concrete modification with complex organomineral additives based on technogenic pozzolans and surfactants [dissertation]. Moscow; 2015. 372 p. (in Russian).

5. Kaprielov S.S., Sheinfeld A.V., Krivoborodov Yu.R. Influence of the structure of cement stone with the addition of microsilica and superplasticizer on the properties of concrete. Beton i zhelezobeton [Concrete and reinforced concrete]. 1992;(7):4–7 (in Russian).

6. Kuntsevich O.V. Concrete of high frost resistance for buildings in the Far North. Leningrad: Stroyizdat Publ.; 1983 (in Russian).

7. Shtark I., Wicht B. Frost resistance and resistance of concrete to frost and thawing salt. In: Durability of concrete. Kyiv: Oranta Publ.; 2004. pp. 200–246 (in Russian).

8. Fagerlund G. The influence of slag cement on the frost resistance of the hardened concrete. Stockholm: Swedish Cement and Concrete Research Institute; 1982.

9. Wenzel B.I., Egorov E.A., Zhizhenkov V.V., Kleiner V.D. Determination of ice melting temperature in porous glass depending on the pore size. Journal of Engineering Physics. 1985;48(3):346–350. https://doi.org/10.1007/bf00878204

10. Stolnikov V.V. On the theoretical foundations of the resistance of cement stone and concrete to alternating cycles of freezing and thawing. Leningrad: Energiya Publ.; 1970 (in Russian).