Effect of Varying Steel Fiber Content on Strength and Permeability Characteristics of High Strength Concrete with Micro Silica.

Babar Ali,Rawaz Kurda,Hawreen Ahmed,Bengin Herki,Rayed Alyousef,Muhammad Fayyaz Ul-Haq,Ali Raza,Rasheed Mustafa,Ahmed Mohammed

doi:10.3390/ma13245739

Abstract

For the efficient and durable design of concrete, the role of fiber-reinforcements with mineral admixtures needs to be properly investigated considering various factors such as contents of fibers and potential supplementary cementitious material. Interactive effects of fibers and mineral admixtures are also needed to be appropriately studied. In this paper, properties of concrete were investigated with individual and combined incorporation of steel fiber (SF) and micro-silica (MS). SF was used at six different levels i.e., low fiber volume (0.05% and 0.1%), medium fiber volume (0.25% and 0.5%) and high fiber volume (1% and 2%). Each volume fraction of SF was investigated with 0%, 5% and 10% MS as by volume of binder. All concrete mixtures were assessed based on the results of important mechanical and permeability tests. The results revealed that varying fiber dosage showed mixed effects on the compressive (compressive strength and elastic modulus) and permeability (water absorption and chloride ion penetration) properties of concrete. Generally, low to medium volume fractions of fibers were useful in advancing the compressive strength and elastic modulus of concrete, whereas high fiber fractions showed detrimental effects on compressive strength and permeability resistance. The addition of MS with SF is not only beneficial to boost the strength properties, but it also improves the interaction between fibers and binder matrix. MS minimizes the negative effects of high fiber doses on the properties of concrete.

Highlights

Plain cement concrete (PCC) is the most versatile construction material owing to its multiple benefits i.e., high compressive strength, cost-efficient, in-situ formability, thermal and electrical insulation, imperviousness, etc
These results show a mixed effect of steel fiber (SF) on compressive strength (CS) at different change in CS with the varying SF dose
These results show a mixed effect of SF on CS at different doses

Summary

Introduction

Plain cement concrete (PCC) is the most versatile construction material owing to its multiple benefits i.e., high compressive strength, cost-efficient, in-situ formability, thermal and electrical insulation, imperviousness, etc. Zain et al [4] showed that the STS/CS ratio decreases as the strength class of concrete is upgraded, high strength PCCs are more vulnerable to brittle failure than normal strength PCCs. PCC has low energy absorption capacity (or toughness) under both tensile and compressive loadings [5,6]. PCC has low energy absorption capacity (or toughness) under both tensile and compressive loadings [5,6] It undergoes a sudden failure after carrying the load beyond its peak capacity and it has very low residual strength (almost negligible compared to fiber-reinforced concrete) [7]. Due to the inherent weakness of PCC under tensile loadings, large structural dimensions cannot be avoided unless it is reinforced with some high strength material i.e., steel rebars, glass fiber-reinforced polymers (GFRP) bars, carbon fiber-reinforced polymer (CFRP) bars, etc

Methods

Results

Conclusion