Experimental and analytical study of hybrid fiber reinforced concrete prepared with basalt fiber under high temperature.

Summary: The usage of mineral basalt fibers is a relatively novel and popular topic nowadays due to its abundant availability, low cost, and higher temperature resistance. In addition, the establishment of analytical models is beneficial because the experimental work is more time‐consuming and expensive. Therefore, in this study, the inorganic mineral basalt fibers with different length and content in hybrid fiber concrete composite are investigated to assess its suitability at room temperature and under high temperature. In addition, a new analytical model for stress‐stain curve of hybrid fiber concrete composite is developed and compared with the models in previous studies. The microstructure examination is also conducted after exposure to high temperature to explore the fiber morphology and interaction with matrix. The substantial improvement was indicated by addition of basalt fiber in hybrid fiber concrete for stress‐strain response, peak stress, elastic modulus, peak strain, ultimate stain, toughness, and specific toughness at room temperature and at 850°C. It was revealed that the basalt fiber had demonstrated overall good appropriateness in the hybrid fiber concrete composite for all the compressive properties. Moreover, the proposed analytical model could be useful for prediction of analytical behavior from experimental data under high temperature for the research and design purposes. [ABSTRACT FROM AUTHOR]