Experimental Research On Durability Of Damaged Concrete Beams Strengthened With BFRP Under Salt And Alkali Environment

Coastal and saline region of reinforced concrete bridges in our country, theinevitable will be affected by salt, alkali corrosion environment. Part of the bridgesusing only a few years have given rise to steel corrosion, concrete fall off, seriouslyaffecting the carrying capacity of the bridge and durability. BFRP (basalt fibercomposite materials) is a new type of inorganic material with light weight, highstrength, resistance to fatigue and corrosion and other significant advantages in thefield of bridge strengthening having broad application prospects. In this paper,influence on durability of FRP reinforced concrete structure under salt and alkalienvironment was analyzed by experiments, as a bridge structure anticorrosion、reinforcementto provide reliable basic data and theoretical support.The research work of this paper is in the key project of natural science fund ofTianjin (fund number12JCZDJC28900) and Tianjin science and technology start seaproject funding (fund number KJXH2012-19).The main studies in this paper wereshown as follows:1. Basalt fiber reinforced concrete beam deflection changes, crack formation anddevelopment of the load-strain distribution as well as the destruction form ofreinforced concrete beams under the salt, alkali conditions were studied. The testresults show that the test results show that the basalt fiber reinforced concrete beamcan obviously reduce trabecular midspan deflection, effectively restrain the formationand development of cracks, and suggest layer of strengthening engineeringapplication are obtained.2. The impact of salt environment on concrete beams reinforced with BFRP wasstudied by controlling the basalt fiber cloth reinforcement layer and salt solutionconcentration. Test results show that salt environment on durability of reinforcedconcrete beam has a certain influence, and bearing capacity of reinforced beamdecreases with increasing concentration of salt solution.3. The impact of alkali solution on concrete beams reinforced with BFRP was studiedby controlling the basalt fiber cloth reinforcement layer and PH value. Test resultsshow that alkali environment on durability of reinforced concrete beam has a certaininfluence.