Combining different fiber types may improve the mechanical properties of fiber reinforced concrete. The present study is focused on investigating hybrid fiber reinforced concrete (HFRC) with steel and basalt fiber. Mechanical properties of fiber reinforced fine-grained concrete are investigated. The results demonstrate that using optimal steel and basalt fiber reinforcement ratios avoids concrete mixtures’ segregation and improves their homogeneity. Concrete with hybrid steel and basalt fiber reinforcement has higher strength. Effective methodology for proper design of HFRC compositions was proposed. It is based on the mathematical experiments planning method. The proposed method enables optimal mix proportioning of high-strength fine-grained concrete with hybrid steel and basalt fiber reinforcement.

Design of optimal concrete compositions with specified quality indicators at minimal cost still remains one of the most actual problems. The paper deals with methodology for designing optimal fiber reinforced concrete composition using experimental-statistical models of concrete properties. The obtained mathematical models for compressive and flexural strength of steel fiber reinforced concrete and a model of superplasticizer consumption are used. The proposed method of fiber reinforced concrete composition design takes into account the specific characteristics of the studied materials. It allows relatively easy composition optimization by applying a specific minimum cost criterion. Experimental results obtained in the frame of the study confirm efficiency of the proposed concrete mix design methodology for producing steel fiber reinforced concrete with necessary properties.

No abstract

No abstract

Adding different fiber types may yield improvement of steel fiber reinforced concrete (SFRC) features. Therefore, the investigation of hybrid fiber reinforced concrete (HFRC) mechanical properties is relevant. The effect of adding hybrid steel and basalt fiber on the mechanical properties of fine-grained concrete is studied. It is shown that hybrid fiber reinforcement using optimal steel and basalt fiber ratio allows preventing concrete mixtures' segregation and improving their structure homogeneity. This, in turn, allows achieving higher concrete strength values. In most cases, the design of such concrete compositions is based on engineering experience that limits the designers' capabilities. Therefore, an effective methodology for proper HFRC composition design should be developed. The present study is focused on developing such a methodology. The developed methodology includes using the mathematical experiments planning method to design optimal composition of high-strength fine-grained fiber reinforced concrete with hybrid steel and basalt fiber reinforcement. It is demonstrated that the proposed method can be effectively used for the design of optimal compositions of HFRC.