EXPERIMENTAL STUDY ON PRESTRESSED CFRP FLEXURAL METHOD OF RC BEAM BASED ON EARLY WARNING THEORY

Aiming at the problem that the ductility of the prestressed CFRP strengthened members is obviously reduced, the safety reserve is insufficient, and there is no obvious omen before the damage, a prestressed CFRP bending reinforcement design method based on early warning theory was proposed. In this method, a clear early warning signal can be given by the break of the self-warning fuse when the actual safety reserve of the reinforcing member is lower than the designed target value. In order to study whether the component after reinforcement by using the design method can emit a clear early warning signal and whether the safety reserve can meet design requirements by defining reasonable yield point of components, four reinforced concrete beams were produced and tested for bending resistance. The test results showed that, when the safety reserve was lower than the design value, the fuse was detached from the beam after the fuse fractured, and an early warning signal was issued; the yield point of the component determined by the farthest method and the mapping method was consistent with the warning point. After evaluation by K₀ and K_eq, the yield point of the pre-warning point as the reinforcing member was more reasonable than the traditional method, and the safety reserve of the components could meet the requirements.