Research on Fatigue Residual Bearing Capacity of Prestressed Concrete Beams Considering Size Effect

Abstract

In order to study the interaction mechanism of fatigue damage and size effect of prestressed concrete beams under fatigue load, multi-stage variable amplitude fatigue tests of three groups of prestressed concrete beams with different sizes were carried out. Through the research and analysis of the test data of prestressed concrete beams under fatigue load, it is found that due to the action of fatigue cyclic load, there is a size effect in the residual bearing capacity of prestressed concrete beams, that is, the increase of residual bearing capacity of prestressed concrete beams decreases with the increase of section size. Considering the influence of size and the degree of fatigue damage, the coefficient of the original formula is modified, and the new calculation formula of residual bearing capacity is basically consistent with the change of the measured results of the specimen.