Triaxial mechanical properties and microstructure visualization of BFRC

Abstract

The addition of basalt fiber can effectively improve the macroscopic performance of concrete. At present, there are few studies on the micro-action mechanism of basalt fiber. In this paper, the triaxial mechanical properties of basalt fibers reinforced concrete (BFRC) are investigated, and the internal microstructure of BFRC is studied with the aid of X-ray Computerized tomography (CT technology), digital image processing technology (DIP) and SEM to study the reinforcement mechanism of basalt fibers on concrete from a microscopic point of view. The study showed that the peak stresses under the same peri-pressure showed an increasing and then decreasing trend with the fiber dosage, and the optimum fiber dosage was 3 kg/m3; the excessive addition of fibers led to the increase of internal pores, the contact probability increased, and the peak stresses decreased. The influence to the triaxial mechanical properties of BFRCs were ranked by the fiber dosage, lesser extent and fiber orientation. In this paper, the study of basalt fiber toughness enhancement from both concrete matrix defects and fiber distribution can further advance the application of ductile concrete composites research.