Recent Literature on Steel Fiber Role in Resistance Improvement of Fibrous Concrete to Repeated Impacts

Abstract

Concrete is a brittle material when subjected to design and accidental impact loads, which are expected along the life span of the structure. To improve the impact performance of concrete, steel fibers are used as short discrete material reinforcing elements. Among the available impact test, the ACI 544-2R repeated impact test is considered as the simplest and cheapest test procedure that needs no sophisticated sensors and costly techniques, which is used as a qualitative tool to evaluate the impact of fibrous concrete. This article introduces a state-of-the-art literature review of the repeated impact performance of steel fiber-reinforced concrete. Rich literature of different steel fiber-reinforced concrete types is reviewed and the effect of steel fibers on the retained cracking and failure impact numbers is highlighted. The sole effects of the geometrical parameters of steel fibers were analyzed in addition to fiber content. Based on the reviewed literature works, it can be summarized that increasing the fiber content increases the bond strength, and using longer fibers affords deeper anchorage lengths inside the cement paste across cracks, which postpone their widening and improves the impact resistance in terms of recorded cracking and failure numbers.