Strength indices and conversion relations for basalt fiber-reinforced recycled aggregate concrete

To analyze the strength indices and conversion relations of basalt fibre-reinforced recycled aggregate concrete (BFRRC), the basic strength indices of BFRRC were tested, and the influence of basalt fibre (BF) content and replacement rate of recycled coarse aggregate on the failure mode and strength indices was analyzed and discussed. A simple and accurate model that involved the replacement rate and BF content was established to predict the conversion relationships among these strength indices, and the existing research results are taken into the presented formula to verify its applicability. The test results indicate that the brittleness of cubic specimens of BFRRC is markedly improved under compression, the typical shear failure of the oblique section occurs in prism specimens, the splitting surface of BFRRC becomes flatter in cubic specimens, and the macroscopic failure mode of the prism specimens belongs to tensile failure under the bending load. All of these strength indices of BFRRC are enhanced by the incorporation of BE The presented conversion relationships have good wide-applicability to calculate the strength indices. The conclusions obtained in the study are of important theoretical value to direct the similar engineering practice.