Experimental Study On Mechanical Properties And Durability Of Basalt Fiber Reinforced Concrete

Basalt fiber are applied in the fiber reinforced concrete due to their good mechanics performance,good high temperature properties,corrosion resistance,low cost,no corrosion occurred during the process.Nowadays,with the extensive applying of BFRC,the experiment and research of it has been concerned and valued by the scholars of internal and overseas.This thesis mainly study and analyze the mechanical properties and durability of BFRC by research, the following conclusions are drawn:①The effect of the volume fraction(0.05%、0.10%、0.15%、0.20%、0.25%、0.30%、0.35%)of basalt fiber on the workability and mechanical properties of the BFRC was studied.By means of microstructural analyses,the reinforcement, toughening and anti-cracking mechanisms was studied. The results showed that, the compressive strength、split tensile strength、flexural strength and toughness have different increases as the fiber volume fraction increases, However,the workability of the concrete was reduced.②The effect of different kinds of mineral admixtures(fly ash and slag powder) and mass fractions(5%、10%、15%、20%、25%、30%) on the workability and mechanical properties of the BFRC was studied. Results showed that,suitable amounts of mineral admixtures could improve the workability and 28 day compressive strength,nevertheless,reduces the tensile splitting strength、flexural strength and toughness of the BFRC.③Based on permeability resistance test and microstructure analysis,the volume content of the basalt fiber compact on the impermeability of BFRC was researched,and the impermeability mechanism of the BFRC was discussed. The results showed that:when the content of fiber increased from 0.05% to 0.10%,concrete’s impervious behavior could be improved;when the content of fiber was more than 0.20%, the pore volume ratio and the interfacial transition zone(ITZ) in concrete were increased,and micro cracks may be more popular for this case,So BFRC’s impervious behavior get dropped.④When the content of fiber increased from 0.05% to 0.15%,eroded by H2SO4 solution for 60 d,The Kf(The compressive strength coefficient of corrosion) has kept at about 1.The Kf reduced with the increase of fiber content.When the content of fiber increased from 0.05% to 0.25%,Though the Kf(The splitting tensile strength of corrosion coefficient) <1,but the addition of fiber could slow the rate of loss of the splitting tensile strength, the concrete resistance to sulfate corrosion could be strengthened.