Bending Capacity And Deflection Analysis Of RC Beams With Localized Deterioration Of Bond Strength

Concrete durability is one of the world-wide concerned problems in the field of structure engineering; reinforcement corrosion is already recognized as one of the most important factors which affect the durability of reinforced concrete structures. It is necessary to find methods to estimate the residual bending capacity and deflection of RC beams with localized deterioration of bond strength. Subsidized by the National Natural Science Foundation of China (No.50678101), simply supported RC beams are introduced to elucidate the influence of localized bond deterioration on RC beam's residual bending capacity and deflection. In this paper, theoretical analysis is combined with programming to realize the calculation procedure easily, the calculated results are compared with experimental results and the comparison shows the satisfactory. The main contributions of this thesis are described in the following aspects:1. Bending capacity analysis of RC beams with localized deterioration of bond strength: factors affecting the bending capacity of RC beams with localized deterioration of bond strength are investigated firstly and a conclusion is reached that the incompatibility of reinforcement and concrete which make the steel strain lagging behind the concrete strain is the key factor. Reasonable calculation method based on a new compatibility condition is proposed to estimate the residual bending capacity of partially unbonded RC beams and RC beams with localized deterioration of bond strength. The calculated results are compared with experimental results so as to prove the rationality and accuracy of the calculation method.2. Deflection analysis of RC beams with localized deterioration of bond strength: the foundational influence mechanism of deflection of RC beams with localized deterioration of bond strength is revealed, a simplified deflection computational model of RC beams with localized deterioration or loss of bond strength is proposed. Also, the exploratory research on deflection computational model of continuous beams with localized deterioration of bond strength is tested at the end of chapter 3. The calculated results are compared with experimental results so as to prove the rationality and accuracy of the computational model.3. In order to reduce the difficulty of calculation, all the calculation procedures are realized by programming; in order to make it easier to use the program, interface is introduced and several windows are designed. Finally, software to calculate the residual bending capacity and deflection of RC beams with localized corroded reinforcement is finished.