Title: Structural Performance of Self-Consolidating Engineered Cementitious Composite Beams Containing Crumb and Powder Rubber
Author(s): Assem A. A. Hassan
Publication: Materials Journal
Appears on pages(s): 167-179
Keywords: cement-based composites; crumb and powder rubber; ductility; energy absorption capacity; large-scale beam
This study investigated the structural behavior of large-scale rubberized self-consolidating engineered cementitious composite (SCECC) beams designed to fail in shear. Specifically, the experimental program focused on the use of crumb rubber (CR) and powder rubber (PR) in SCECC as a partial replacement of silica sand at replacement levels of 0, 10, 20, and 30% (by volume). All cast SCECC, SCECC-CR, and SCECC-PR beams were compared with the performance of normal self-consolidating concrete (SCC) beam (containing coarse aggregates) at comparable compressive strength. The results obtained from this study included the fresh and mechanical properties of the developed mixtures, in addition to load-deflection curves, cracking behavior, first flexural crack load, diagonal crack load, ultimate load, ductility, and energy absorption capacity of the tested beams. The performance of some code-based equations in estimating the ultimate capacity and cracking moment of the tested beams was also evaluated. The results showed that all SCECC, SCECC-CR, and SCECC-PR beams exhibited higher performance compared to that exhibited by the normal SCC beam. However, the inclusion of either CR or PR in SCECC led to a reduction in the first crack load, diagonal crack, and ultimate load capacity of SCECC. The ductility and energy absorption capacity of SCECC was found to increase when 10% CR was introduced, while further increase in the percentage of CR decayed both the ductility and energy absorption capacity. On the other hand, the use of PR with up to 30% contributed to improving the deformability of the SCECC beam with no significant loss in its load-carrying capacity, thus providing a sustainable composite with higher ductility and energy absorption.