Flexural behavior of reinforced concrete beams made of normal and polypropylene fiber-reinforced concrete containing date palm leaf ash

Abstract

Nowadays, the fast development of the construction industry and the growing need for constructional material along with the emerging concerns about the environmental issues have pushed researchers to consider and investigate the possible use of local, recycled, and waste materials as an alternative in the production of new building materials. Concrete is one of the widely used constructional materials and cement is its main component. Cement production is a highly energy-consuming process that emits a considerable amount of greenhouse gasses into the atmosphere. Therefore, partly replacing cement with other cementitious materials can reduce energy consumption and environmental pollution. In the present study, the effects of Date Palm Leaf Ash (DPLA) on the mechanical properties of Polypropylene Fiber Reinforced Concrete (PFRC) are investigated experimentally. For this purpose, different cubic, cylindrical, and beam specimens of Normal Concrete (NC) and PFRC with various DPLA replacement ratios (1%, 3%, 5%, 10%, and 15%) are cast for the compressive, tensile splitting and four-point bending tests, respectively. The effects of the DPLA on the mechanical properties, cracking and failure behavior of NC and PFRC is evaluated by performing tests on a total of 117 specimens. According to the obtained results, the addition of DPLA to concrete has a positive effect on the compressive and flexural strength of hardened concrete, as well as its toughness. Moreover, it is observed that DPLA improves the ductility of concrete. Based on the test results, the optimum value of the DPLA replacement ratio is equal to 3% and 5% for the compressive and flexural strength, respectively. Finally, based on the attained results, predictive models are proposed to determine the tensile strength of normal and fiber-reinforced concrete containing DPLA.