Development of green and sustainable ultra-high-performance concrete composite reinforced with date palm fibers

Abstract

In a sustainable approach, it is essential to reduce the volume of agricultural waste materials in order to minimize environmental and health concerns. To pursue this goal, agricultural wastes, mainly date palm fibers (DPFs), was used as a partial replacement of conventional steel fibers to produce ultra-high-performance concrete (UHPC). The UHPC has been used to describe a steel-fibers-reinforced cementitious composite with a very low water-binder ratio. It is one of the most significant breakthroughs in concrete technology in the 20th century due to its outstanding mechanical performance, such as compressive strength over 150 MPa and flexural strength over 30 MPa. The cost of UHPC is known to be significantly higher compared to ordinary reinforced concrete because it requires large quantities of steel fibers. This paper aims to study the feasibility of utilizing DPFs as a partial replacement of steel fibers to produce green, low-cost and sustainable UHPC. The process of extraction and treatment of the DPFs before incorporating it into the mix design was discussed. Several concrete samples were prepared with different weight percentages of DPFs as a partial replacement of steel fibers (from 0% to 25 wt.%). Compression strength, flexural strength, water absorption, and fresh/hardened densities were experimentally investigated. The morphology and the bonding interface between the fibers and cementitious composite were characterized by scanning electron microscopy (SEM). The results reveal that the DPFs has the potential to be utilized to produce UHPC with comparable performance to the traditional UHPC that is normally reinforced with steel fibers.