Bridge infrastructure in coastal areas is deteriorating at an accelerated pace due to increased traffic and aggressive environments. Traditional black steel reinforcement in bridges is corroding due to exposure to saline environments. This leads to structural failure which may cause personal damage, and financial losses. To overcome the problem with corrosion, Fiber Reinforced Polymer (FRP) reinforcement bars are used in civil structures as a replacement to the steel rebars because of their noncorrosive properties. FRP rebars are a product of composite materials which are made from combining fibers and resin matrices. In the U.S., many projects have focused on aramid, carbon, and glass FRPs for applications in civil infrastructure for the past two decades. Research on basalt FRP rebars was abandoned in early 1930s due to historical reasons. However, due to its superior characteristics (strength performance, corrosion resistance, temperature range, and durability) basalt rebars have gained a renewed interest in recent years. Due to these properties, Basalt FRP bars are capable of replacing steel rebars, and glass fiber rebars in bridge engineering applications. Though BFRP rebars have superior material properties, a number of BFRP products with inferior quality are available in the global market as material standards are not available. Standardizing the BFRP rebar products helps in eliminating the products of inferior quality and protecting the general public safety. Because rebars are intended to be used in marine structures which are high in pH and have high saline concentrations, a wide range of raw materials and rebar products should be exposed to several combinations of aggressive conditions and their long-term strength and durability characteristics should be experimentally studied. Experimental evaluations on the fiber, sizing, and resin level are needed to promote the standardization process of BFRP Rebars. In this research, the properties of basalt fiber reinforced polymer (BFRP) rebars, and the raw materials used in manufacture of rebars were studied. This involved analysis of physical, mechanical, and durability properties of rebars and raw materials. In addition, standard specifications for the use of these rebars in concrete structures were proposed. In the first part of this study, physical and mechanical properties of rebars and their components were studied by conducting preliminary tests on them, which included measurement of the cross-sectional properties, fiber content, moisture absorption properties, XRF analysis, glass transition temperature, tensile strength, transverse, and apparent horizontal shear strength, and bond strength of rebars. Tensile strength of resin and XRF analysis on fibers were also conducted to study the initial material properties. It was found that the virgin properties all tested rebars have satised and surpassed the existing criteria for GFRP rebars by at least 120%. For the second part of this research, a test matrix was developed to understand the durability properties of the rebars and the resin matrices. Rebars and components were then exposed in the aggressive environments at 60°C for 300d. A series of physical and mechanical tests were performed on rebars and components as well as various chemical tests on exposure environments were conducted to study the property changes. It was noticed that the sizing on the fibers and resin matrix played a key role in protecting the rebars from degradation in aggressive environments. A long-term prediction model which can predict strength retention of FRP bars in any type of aggressive environment and any exposure temperature was developed based on fib Bulletin 40 model with additional degradation factors addressing different Cl concentrations in the exposure environments and exposure time. The results showed that tested BFRP rebars outperformed GFRP rebars in all aspects and the results showed that BFRP rebars can be used in future marine structures. While it was suggested that specifications for these rebars be inline with GFRP rebar specifications, with additional data, the specfications for these rebars can be set higher than GFRP rebar specifications.
