Concerning the problem of assigning the compositions of steel fiber-reinforced concretes

Conclusions

• 1. A considerable increase of the content of sand in comparison with ordinary concrete mixes is required for preparing workable fiber-reinforced concrete mixes. The optimal content of sand should be selected experimentally in relation to the particular properties of the aggregates and length, cross section, and content of fiber. Fiber can be regarded as a coarse aggregate of acicular form with a developed surface, for binding of which an increased quantity of the mortar component is necessary.

• 2. When using fiber in the form of wire lengths without additional anchorage on the ends, its length can be taken equal to 60–65 diameters without a substantial decrease of the tensile strength of the fiber-reinforced concrete. A reduction of the length of the fiber to these limits considerably decreases clumping of the fiber during mixing.