Experimental and Numerical Investigations on the Impact Response of MiniBar Reinforced Concrete Columns

Fibres have been increasingly used in the construction industry in the past years. Fibres are added to the concrete mix to improve flexural tensile strength and control the cracking propagation of concrete. Typical fibres used in concrete are steel, basalt, and glass fibres. Similar to steel reinforcing bars, steel fibres are the most widely used fibres in concrete. However, steel fibres are high in density, and they also reduce the workability of wet concrete mixed. They are also not suitable for use in a corrosive environment such as offshore applications. Alternatively, basalt fibres with lightweight, high-strength, and noncorrosive properties can be used. Apart from the normal chopped basalt fibres, basalt fibre MiniBars have also been proposed and used in concrete structures recently. MiniBars are made of basalt fibre with an average diameter and length of about 0.7 mm and 41–45 mm, respectively which act like scaled basalt fibre-reinforced polymer reinforcing bars. In this study, the dynamic response of MiniBar-reinforced concrete columns under pendulum impacts is investigated. Test results show that the addition of MiniBars can improve the impact capacity of the reinforced concrete columns. A numerical model is also developed and validated with the test results. The numerical model can be further used to conduct parametric investigations of various impact scenarios.