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

Abstract

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 BF. 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