Deflection analysis of pre-stressed concrete beam with local corrosion

In order to investigate the influence of local corrosion on the deflection of pre-stress concrete beam, the advanced curvature integral method and the step stiffness method are introduced in this paper, the calculation results are compared with the tested results and the measuring results of practical bridge. At last, the influence of parameters such as the corrosion rate, length of corrosion area, corrosion location and reinforcement ratio on the deflection of local corroded PC beam are analyzed. The results show that the advanced curvature integral method can predict the deflection of corroded tested PC beams and the real main beam of bridge, and which is more accurately than step stiffness method, but the calculated time of step stiffness method is significantly reduced and meeting the needs of engineering inspection for calculating the deflection of real bridge. When the corrosion rate reaches 15 %, the corrosion rate is the main parameter affecting the flexural stiffness of PC beam. For the local corrosion length from 0.5 m to 2 m, the deflection of PC beam with different corrosion length is relatively close. For bridges where the corrosion length is less than 50 % of beam length, the calculation results will be too conservative if the effect of corrosion length is omitted. When the reinforcement rate exceeds 3.5 %, the reduction of deflection is decreased. The local corrosion has a more significant effect on PC beam with lower reinforcement rates.