Evaluation of post-cracking behavior of fiber reinforced concrete using indirect tension test

Abstract

This paper presents an experimental investigation on the applicability of the novel double-edge wedge splitting (DEWS) testing technique to evaluate the mechanical properties of fiber reinforced concretes (FRCs) with low fiber content. This study aims to validate the DEWS test for the structural evaluation of FRCs with softening behavior, which is also considered by the design codes for structural applications. In this case, the occurrence of post-peak instability is critical. This instability could compromise the residual strength evaluation, especially for the serviceability limit state (SLS). The experimental studies focused on three main aspects affecting the DEWS test response: effect of test displacement rate, effect of fiber content, and orthotropy of FRCs. Two different groups of FRCs (reinforced with steel and macrosynthetic fibers) were mechanically evaluated, both at the SLS and ultimate limit state. The variation of the test displacement rate had no significant impact on the FRC post-cracking pattern. The DEWS test could detect behavioral variations induced by altering the fiber content and fiber orientation on both composites. This variation was more evident for higher crack opening levels because the post-peak instability may compromise the DEWS results in the SLS.