The Experimental Assessment of the Impact of Kevlar Fibers in Improving the Resistance Properties and Permeability of Concretes Containing Nano-silica

Document Type : Original Article

Authors

Assistant Professor, Department of Civil Engineering, Mahabad Branch, Islamic Azad University, Mahabad, Iran.

10.22125/iwe.2023.414738.1745

Abstract

One of the characteristics of concrete as a brittle material is its low tensile strength and brittleness, so it needs to be strengthened to be used as the most basic building material. In fiber-reinforced concrete, thousands of tiny fibers are randomly scattered and distributed throughout the concrete during mixing, this improves the properties of the concrete in all respects. In this research, the aim is to investigate the role of Kevlar fibers in improving the compressive resistance, tensile strength and permeability of Nano-silica concretes. The concrete samples made have 4% of Nano-silica and the ratio of water to cement in this design is equal to 0.32 and the amount of Kevlar fibers used is 0, 0.10, 0.20, 0.30 and 0.40% by volume of concrete. The results of the compressive resistance test show that in these tests, by adding 0.10% of fibers (optimal percentage), the compressive resistance improves by 28, 24, and 23% at the ages of 7, 28, and 90 days, respectively. From the results of the tensile strength tests, it was found that by adding 0.30% of fibers (optimal percentage), the tensile strength of the samples increases by 64%. The permeability test was performed using the Penetration Method, which showed a 30% improvement in water permeability in samples containing 0.20% of fibers (optimal percentage).

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