Experimental data on the strength and deformability of concrete class B25 taking into account the variable loading rate of prismatic samples under central compression
Abstract
Experimental data on the strength and deformability of concrete class B25 taking into account the variable loading rate of prismatic samples under central compression
Incoming article date: 26.07.2025The paper presents an analysis of experimental data reflecting the influence of the loading rate on the strength and deformation characteristics of concrete of class B25 under conditions of central compression. 12 prismatic samples with dimensions of 100×100×400 mm, distributed in three series with different load application rates, were prepared and tested for the study. Statistical data processing, including analysis of variances and the construction of regression models, allowed not only to predict the behavior of concrete under various loading conditions, but also to confirm the theoretical prerequisites associated with the dynamic hardening of the material. The high values of the correlation coefficients (up to 0.9943) and determination (up to 0.9922), as well as the Fisher criterion, which significantly exceeds the tabular thresholds, characterize the high reliability of the results obtained, indicating an increase in concrete strength with an increase in loading speed and a simultaneous decrease in its deformability. The derived dependences can serve as an experimental basis for the development of a nonlinear deformation method for calculating bent and non-centrally compressed reinforced concrete structures made of concrete of this class (B25), subject to short-term impacts, including classical static loads, as well as dynamic loads of medium duration, characteristic of the operating conditions of structures under the influence of factors such as the movement of overhead cranes along crane beams or the passage of fire trucks along the overpass. The results obtained contribute to a more accurate consideration of dynamic effects in the design and calculation of reinforced concrete structures operated in such conditions.
Keywords: experiment, concrete samples, central compression, loading rate, strength, marginal relative deformations, dynamic hardening, correlation and regression analysis