English：

The mechanical properties of modified polyurethane concrete are, however, not clear,especially the understanding of its fatigue performance, which is still very weak. The flexural strength andflexural fatigue properties of a new type of modified polyurethane concrete at room temperature werestudied. Firstly, the cuboid modified polyurethane concrete specimens were prepared, and the flexuralstrength was obtained by flexural test. Then, the four⁃point bending fatigue test of the modifiedpolyurethane cuboid specimen was carried out to obtain its fatigue life under cyclic loading. Finally, thefatigue equation of modified polyurethane concrete was established by introducing the concept of failureprobability. The results indicate that the fatigue failure mode of modified polyurethane concrete is brittlefailure, and its fatigue life follows the two⁃parameter Weibull distribution. By constructing the doublelogarithmic fatigue life equation under different failure probabilities, the analysis method and basic data ofthe fatigue performance of modified polyurethane concrete are established.