Mechanical Properties of Nano-CaCO₃ and Basalt Fiber Reinforced Concrete: Experiments and Numerical Simulations

Abstract

In this study, the compressive, split tensile, and flexural strengths of concrete with nano-CaCO₃ only were compared with those of concrete with nano-CaCO₃ and basalt fibers through field experiments, and the underlying mechanisms were analyzed by the Scanning Electron Microscope (SEM) techniques. On the mesoscale, a damage model of concrete was established based on the continuum progressive damage theory, which was used to investigate the influence of different lengths and contents of fibers on the mechanical properties of concrete. Then, the experimental and numerical simulation results were compared and analyzed to verify the feasibility of model. The results show that nano-CaCO₃ can enhance the compressive strength of the concrete, with an optimal content of 2.0%. Adding basalt fibers into the nano-CaCO₃ reinforced concrete may further enhance the compressive, split tensile, and flexural strengths of the concrete; however, the higher content of basalt fiber can not lead to higher performance of concrete. The optimal length and content of fiber are 6 mm and 0.20%, respectively. The SEM result shows that the aggregation of basalt fibers is detrimental to the mechanical properties of concrete. The numerical simulation results are in good agreement with the experimental results.

Keywords

concrete / nano-CaCO₃ / basalt fiber / mechanical property / microscopic characterization / numerical simulation