Due to the development of the construction industry and the need to build lighter structures and elements with more delicate geometry in high-rise buildings, and on the other hand, for seismic improvement of existing concrete buildings, the construction of elements with smaller dimensions and longer useful life has required engineers to build concrete with higher strength and efficiency and lower curing costs.

Studies conducted in this regard in recent years have led to significant progress in improving the compressive and tensile strength of concrete, leading to the emergence of "ultra-strong" concretes with compressive strengths above 150 MPa (1500 kg/cm2). One of the most important aspects of these concretes is their resistance to aggressive agents such as chloride ions and freeze-thaw cycles. In this research, micro steel fibers, type I cement with a strength class of 52.5 kg/cm2, silica sand, silica fume, polycarboxylate-based superplasticizer, and water were used to increase the strength and improve the ductility of the manufactured structural elements. Five different mixing designs were investigated - for deliberate curing, no steam chamber was used for curing the concrete. The curing of the samples was the same and the concrete life was examined at 7 days and 28 days. Then, Brazilian compressive and tensile strength tests were taken from the samples and the optimal sample in question showed a compressive strength of 154 and a tensile strength of 21 MPa.

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Due to the development of the construction industry and the need to build lighter structures and elements with more delicate geometry in high-rise buildings, and on the other hand, for seismic improvement of existing concrete buildings, the construction of elements with smaller dimensions and longer useful life has required engineers to build concrete with higher strength and efficiency and lower curing costs.

Studies conducted in this regard in recent years have led to significant progress in improving the compressive and tensile strength of concrete, leading to the emergence of "ultra-strong" concretes with compressive strengths above 150 MPa (1500 kg/cm2). One of the most important aspects of these concretes is their resistance to aggressive agents such as chloride ions and freeze-thaw cycles. In this research, micro steel fibers, type I cement with a strength class of 52.5 kg/cm2, silica sand, silica fume, polycarboxylate-based superplasticizer, and water were used to increase the strength and improve the ductility of the manufactured structural elements. Five different mixing designs were investigated - for deliberate curing, no steam chamber was used for curing the concrete. The curing of the samples was the same and the concrete life was examined at 7 days and 28 days. Then, Brazilian compressive and tensile strength tests were taken from the samples and the optimal sample in question showed a compressive strength of 154 and a tensile strength of 21 MPa.