Research on Dynamic Mechanical Properties and Constitutive Model of Basalt Fiber Reinforced Concrete after Exposure to Elevated Temperatures under Impact Loading

Wenbiao Liang,Yan Li,Yue Zhai,Yubing Yang,Zhou Wang,Junhai Zhao

doi:10.3390/app10217684

Abstract

The dynamic mechanical properties of basalt fiber reinforced concrete (BFRC) with different fiber contents (0.0%, 0.1%, 0.2%, 0.3%, 0.4%), confining pressures (0 MPa, 5 MPa, 10 MPa, 15 MPa) and exposed to different temperatures (20 °C, 200 °C, 400 °C, 600 °C, 800 °C) were investigated by using a 50 mm split Hopkinson pressure bar (SHPB) apparatus, and the factors such as fiber content, temperature and confining pressure effect on the dynamic mechanical properties were analyzed. The results show that the dynamic peak stress increases first and then decreases with the increase of fiber content. At different temperatures, the peak stress and its corresponding strain correspond to different fiber content, and the optimal fiber content is between 0.1% and 0.3%. When the temperature was from 20 °C to 400 °C, the dynamic peak stress decreased less, while when the temperature reached 600 °C and 800 °C, the dynamic peak stress decreased greatly. The confining pressure can significantly increase the dynamic peak stress and change the crushing morphology of specimens. The damage variable was built based on the Weibull distribution. A dynamic damage constitutive model combining statistical damage and viscoelastic model was established based on component combination model. The fitting curve of this model fitted well with test curve by identifying fewer undetermined parameters compared with Zhu-Wang-Tang (ZWT) model; therefore, this model can well describe the dynamic properties of BFRC under impact load.

Highlights

Basalt fiber (BF) is a typical silicate fiber with outstanding high temperature resistance, good compatibility with cement and concrete, superior mechanical properties and high chemical stability [1,2,3].The manufacturing process of BF consumes less energy and no additives, which makes it cheaper than glass or carbon fiber [4]
Basalt fibers have been used as concrete reinforcement due to their superior performance and a lot of research has been conducted on it
The dynamic mechanical properties of basalt fiber reinforced concrete (BFRC) were investigated by using a split Hopkinson pressure bar (SHPB) apparatus

Summary

Introduction

Basalt fiber (BF) is a typical silicate fiber with outstanding high temperature resistance, good compatibility with cement and concrete, superior mechanical properties and high chemical stability [1,2,3].The manufacturing process of BF consumes less energy and no additives, which makes it cheaper than glass or carbon fiber [4]. Basalt fiber (BF) is a typical silicate fiber with outstanding high temperature resistance, good compatibility with cement and concrete, superior mechanical properties and high chemical stability [1,2,3]. Basalt fibers have been used as concrete reinforcement due to their superior performance and a lot of research has been conducted on it. As a kind of concrete reinforced composite material, BFRC has higher strength, toughness and better impact resistance than ordinary concrete, because the randomly distributed fibers form networks to hinder the formation and expansion of micro and macro cracks [2,5,6,7,8]. In recent years, the application of BFRC has been expanding continuously, such as underground engineering, protection engineering, etc.

Methods

Results

Conclusion