Relationship between compressive strength and sample shape, size of concrete and determined by weighted maturity method

In this study, the relationship between the compressive strength of concrete with different strength classes, maximum aggregate sizes, sample shapes and sizes was determined and the compressive strengths obtained from fresh concrete and hardened concrete were compared with the compressive strengths obtained by the maturity method in fresh concrete. Within the scope of the study, concrete production was made with three different maximum aggregate size (Dmax) and three different concrete classes. C25/30 and C30/37 classes of normal concrete from a mixture with a Dmax of 25 mm, mass concrete in C20/25 strength classes from mixtures with Dmax of 63 and 125 mm were prepared. 10x10x10 cm cube, 15x15x15 cm cube, ø10x20 cm and ø15x30 cm cylinders from concrete mix with Dmax of 25 mm, ø15x30 cm and ø25x50 cm cylinder molds from concrete mix with Dmax of 63 and 125 mm. On the obtained concrete samples, estimated concrete strength test according to TS 13508 standard was carried out by the maturity method in the laboratory and field environment. As a result of the study, the transition coefficients were calculated for the compressive strength of concrete with different maximum grain diameters, strength classes, shapes and sizes. The compressive strength coefficient of the cylindrical specimens with different dimensions (fck ø25x50 / fck ø15x30) was found to be 0,88. The compressive strengths measured from the fresh concrete samples and the cores taken from the hardened concrete were found to be similar with the estimated compressive strengths by the maturity method used in the study. In this context, instead of taking samples from fresh concrete and concrete productions, it was concluded that the compressive strength measurements performed on site by the maturation method in fresh concrete are reliable.