Material properties of basalt fibre reinforced concrete made with recycled earthquake waste

Abstract

Concrete waste constitutes the major proportion of construction waste which counts on about 50% of the total wastes generated. The use of recycled aggregates serves to promote the recycling of concrete in the construction industry as well as to suit the reconstruction need in earthquake areas. This paper presents an investigation on mechanical properties and microstructures of basalt fibre (BF) reinforced recycled aggregate concrete (RAC). The main parameters considered in the study are the replacement ratio of recycled coarse aggregates (RCA) and the content of the basalt fibre. The research work is focused on the influences of the above parameters on the failure mode, compressive strength, tensile strength, elastic modulus, Poisson’s ratio and the ultimate strain of the BF reinforced RAC. The results show that the mechanical properties of RAC can be enhanced by using BF. The SEM observations of the concrete reveal that the BF accumulated in pores and on the surface of the attached mortar can not only strengthen the RAC, but also improve the microstructure of the interfacial transition zone (ITZ), which further enhances the strength and ductility of the RAC. Therefore, the basalt fibre reinforced RAC can be used in construction to reduce the environmental hazards from a large amount of earthquake waste from collapsed buildings.