| The fatigue performance and fatigue life of reinforced concrete beams will be reduced because of the steel corrosion.To solve this problem,the Impressed Current Cathodic Protection(ICCP)and Structural Strengthening(SS)repair methods are always used.One is to prevent the reinforcement from further corrosion,the other is to improve the bearing capacity of the structure.This paper combined the two together,using the excellent mechanical properties and electrical conductivity of carbon fiber as auxiliary anode and structural reinforcement materials to form the ICCP-SS double repair system.This paper studies the fatigue performance and life of the concrete continuous beam under the double repair system through experimental research,numerical simulation and reliability analysis.The fatigue test of the concrete continuous beam under the double repair system is studied.In the fatigue test,five continuous beams were designed,including one uncorroded and unrepaired beam,one corrosion repaired beam and three corrosion repaired beams.By analyzing the failure mode,fatigue life,cracks development,deflection change,and internal force redistribution of the beam,the influence of corrosion and repair mode on the fatigue performance and life of the continuous beam is discussed.The fatigue life prediction model of the concrete continuous beam is established,and the influence of key variables on the fatigue life of the beam is further analyzed through extended simulation.The numerical analysis and fracture mechanics are combined to simulate the fatigue test of the concrete continuous beam,and the fatigue life prediction model is established.According to the life prediction model,the paper takes the corrosion rate,load level and repair mode as variables to carry out the extended simulation,further analyzes the influence of each variable on the fatigue life of concrete beams,and regresses the S-N curve according to the test results.The reliability of the extended simulation specimen is calculated,and the fatigue life of the beam is analyzed from the probability point of view.Considering the great discreteness of fatigue test itself,the reliability analysis of the extended simulation specimen is carried out by the Monte Carlo method.And the reliability-cycle times’ curve is given,which provides a certain reference for the fatigue design of the beam. |
