Effect of steel fibers on the compressive and splitting-tensile behaviors of cellular concrete with millimeter-size pores

A high-performance steel fiber reinforced cellular concrete (SFRCC) with millime-size pore structure is recently suggested as an attractive material in structural engineering because of its desirable engineering characteristics. However, the influence of the steel fibers on the mechanical properties of SFRCC are still very limited in literature. Therefore, before the structural applications, it is necessary to learn the mechanical behaviors of SFRCC under compression and splitting-tension, as well as their relationship. To this end, a detailed experimental program has been performed to research the effect of fibers' shape (i.e., crimped, straight and hooked end) and aspect ratio (i.e., 33.33, 44.44 and 55.56) on the compressive and splitting-tensile behaviors of the new SFRCC utilizing saturated superabsorbent polymer (SAP) under different volume fraction of steel fibers (i.e., 0.5%, 1.0% and 1.5%). Experimental results show that higher compressive strength and splitting-tensile strength of SFRCC are tightly related to higher volume fraction or aspect ratio of steel fibers, corresponding to the more ductile behaviors and higher loading levels in the post-peak behaviors. Moreover, it is important to consider the influence of fibers' shape on the mechanical properties of SFRCC. Based on the cracked planes of SFRCC specimens after splitting-tensile tests, it is confirmed that the procedures of specimen fabrication and material characterization significantly influence the distributions of steel fibers and pores and some empirical formulae are proposed to describe the dependence of their distributions on the fiber characteristics. (C) 2019 Elsevier Ltd. All rights reserved.