High-Frequency Fatigue Performance of Cracked Mortar after Epoxy Grouting Reinforcement

This paper presents the experimental study on the influence of grouting reinforcement on the fatigue behavior of cracked cement mortar under different stress ratio and levels. The compressive fatigue tests were conducted with a loading frequency of about 150 Hz. The fatigue life decreased logarithmically with the increase of the stress level, and the fatigue life threshold increased with the increase of the stress ratio. The pores near the fracture were effectively strengthened after the grouting reinforcement. The initial fatigue crack of the sample was initiated at the original crack tip when the lateral deformation reached its threshold value. A double logarithmic fatigue equation was introduced to delineate the fatigue equation. Considering the influence of stress level and stress ratio, a damage evolution equation was proposed to describe the damage evolution process. The fitting results agreed well with the test data.