Study On Durability Of Fiber Reinforced Polymer Rebar

Fiber reinforced polymer(FRP)bars,which is as a new solution to the corrosion of steel reinforcement in concrete.It is a new compound material with light weight, high tensile strength and strong resistance to corrosion, i. At present,some research work on the durability of Fiber Reinforced Plastic materials has been carried out by domestic and foreign scholars, Study on the durability of GFRP rebar is more than the BFRP rebar by the researchers.Moreover the test in long-term durability of the natural environment are few,.In view of the above,Through the unaccelerated aging and the artificial rapid aging,the durability of Basalt fiber rebar and Glass fiber rebar were studied including the following aspects of the research work;1,Study on the tensile properties and shear performance of FRP rebars Under the Lab environment, determined the Destroying forms, tensile strength, elastic modulus, limit strain, and shear strength of FRP rebars. The results show that there is a large difference between the actual diameter (practical tensile strength) and nominal diameter (name tensile strength),The study on the durability of the FRP bars in this paper, The tensile strength is the practical tensile strength corresponding by nominal diameter; The Destroying forms of FRP bars In the process of tensile is relevant to the diameter, Namely the greater the diameter the damage form approximates to fry scattered type.The FRP bars stretching or shear strength also related with diameter, namely the larger diameter, the smaller the stretching or shear strength;The elastic modulus of FRP bars measured In the testing process are consistent with provide value by the manufacturers(5GPa-41GPa);The limit strain of FRP bars are almost not influenced by diameter, but it is great influenced by its strength.2,The study about the durability of frp bars influenced by the accelerated aging environment (acid, water, alkali, salt solution).the results showed that the intensity of FRP bars is relevant to the time, The longer time,the decrease of strength;The same diameter FRP bars,the tensile strength Dropping of BFRP reinforcement is bigger in acid environment, the tensile strength Dropping of GFRP reinforcement is smaller in water environment,shear strength dropping of FRP is relevant to its tensile strength dropping, with the increase of diameter, the elastic modulus of GFRP rebars in acid environment increased, but contrary to that is BFRP rebars.3,The study on the durability of FRP bars is influenced by natural aging environment.The results show that,with the increase of time, the tensile strength and limit strain of FRP bars generally decrease, but contrary to that is the changement of elastic modulus.The shear strength OF FRP bars also decrease,The degree of reduces concerne with strength. namely, the greater the degree of strength,the smaller strength reduced.4,according to the the comparison and analysis of research results which is from endurance evaluation model of existing FRP bars.Combining the results of this research results, a more reasonable durability evaluation model of FRP bars was improved, which is used to evaluate the more complex durability of FRP bars.