Original scientific paper
Frost resistance of cement-sand and concrete beams during unilateral freezing
Nepomyashchy Alexander Nikolaevich
; Odessa State Academy of Civil Engineering and Architecture
Vyrovoy Valeriy Nikolaevich
; Odessa State Academy of Civil Engineering and Architecture
Chistyakov Artem Aleksaedrovich
; Odessa State Academy of Civil Engineering and Architecture
Abstract
The work investigates changes in the beam structure under the action of local
freezing, which leads to a change of the mechanical properties of the material and,
consequently, of the beam structure. Two types of beam samples were used: from
cement-sand mortar and from concrete. The work investigates the change in the
development of deformations depending on the conditions of freezing of samples.
The second accelerated method for assessing frost resistance was chosen according
to DSTU B В.2.7-47-96. An accelerated method was chosen for assessing frost
resistance at the temperature of -20 ±2 C°. After every five freeze-thaw cycles, the
following changes were monitored: mass, water absorption, ultrasound transmission
rate, damage coefficient, tensile bending strength, splitting strength, compressive
strength, carbonization depth. The results showed that both in concrete and in
mortar samples, the compressive strength after freezing was lower by 8% and 15%
accordingly. The experimental results obtained confirm the assumptions made that
the frost resistance of the material depends on the conditions of exposure of
negative temperatures on products and structures and it can be used in a wider
range of construction which will push regional development.
Keywords
cement-sand mortar; concrete; beam; deformations; localized freezing and thawing; material properties; structural changes
Hrčak ID:
261641
URI
Publication date:
30.8.2021.
Visits: 709 *