Behaviour of Damaged B.F.I. Beam Repaired by CFRP Strips under Static or Fatigue Loads Using Finite Element Simulation

Abstract

This paper presents the numerical study to simulate the fatigue crack growth of artificially damaged steel Broad Flange I- beams section by single edge notched repaired with carbon fiber reinforced polymer CFRP strips. The study is carried out using ANSYS classic modeling approach is suggested to simulate the fatigue response of the beams, based on the cumulative damage theory and strain life method. Experimental test results were compared with FE results obtained. A parametric study was conducted using the validated model. The considered parameters were the number of CFRP strip layers used in the repair, the applied load range, initial crack length at time of strengthening and the thickness of CFRP strip. The numerical results indicated that the CFRP increased the critical crack length at which fracture occurred, and the strengthening was more effective at lower stress ranges. Moreover, the CFRP Strips can substantially delay failure and the results demonstrate the possibility of technique and highlight the importance of early intervention when repairing fatigue critical details. The ultimate load and ductility decreased substantially with increasing initial crack length at the time of installing the strengthening layer. Furthermore, increased capacity was achieved by increase the CFRP thickness and layers.