Informatics Publishing Limited

Peng Zhang ¹, Ya-Nan Zhao ¹, Qing-Fu Li ¹, Tian-Hang Zhang ¹, Peng Wang ¹

Affiliations
1 School of Water Conservancy and Environment Engineering, Zhengzhou University, Zhengzhou 450001, CN

Abstract

A parametric experimental study has been conducted to study the effect of nano-SiO₂ particles and steel fibres on the mechanical properties of the concrete composite containing fly ash. Five different nano-SiO₂ contents (1%, 3%, 5%, 7% and 9%) and five different steel fibre contents (0.5%, 1%, 1.5%, 2% and 2.5%) were used. The results indicate that addition of nano- SiO₂ and steel fibres decreases the slump and slump flow of the fresh concrete composite containing fly ash, and both the slump and slump flow decrease gradually with the increase in nano-SiO₂ and steel fibre content. The addition of nano-SiO₂ improves the mechanical properties of concrete composites containing fly ash. There is an increase in the compressive strength and compressive modulus of elasticity with increase of nano-SiO₂ content when it is below 5%, while they begin to decrease after the nano-SiO₂ content is beyond 5%. Steel fibres help improve the mechanical properties of concrete composite containing fly ash and nano-particles. With the appropriate fibre content, the reinforcement of steel fibres on the compressive strength and compressive modulus of elasticity of the concrete composite becomes more obvious as the fibre content increases.

Keywords

Fly Ash, Concrete Composite, Mechanical Property, Nano-SiO₂, Steel Fibre.

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Peng Zhang ¹, Chen-Hui Liu ¹, Qing-Fu Li ¹, Tian-Hang Zhang ¹, Peng Wang ¹

Affiliations
1 School of Water Conservancy and Environment Engineering, Zhengzhou University, Zhengzhou 450001, CN

Abstract

In this article, we study the effect of steel fibre on the fracture properties of high performance concrete (HPC) containing fly ash and nano-SiO₂. The results reveal that the addition of appropriate content of steel fibre helps improve the fracture properties of HPC. Steel fibre improves the fracture parameters of initial fracture toughness, unstable fracture toughness, fracture energy and critical crack opening displacement of the beam specimen of HPC. The results also show that steel fibre has major effect on the fracture curves of the three-point bending beam specimen. The fracture toughness and fracture energy increase gradually, and the area under the fracture relational curve becomes larger when the steel fibre content increases from 0.5% to 2%. However, these fracture parameters begin to decrease and the area under the fracture relational curve becomes smaller when the steel fibre content exceeds 2%. This indicates that steel fibre helps improve the fracture properties of HPC containing nano-SiO₂ and fly ash only when its fibre content does not exceed 2%.

Keywords

Fly Ash, Fracture Properties, High Performance Concrete, Nano-SiO₂, Steel Fibre.

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