Study on mechanical properties of SAC modified ECC material and insufficient reinforcement of lining

In order to find out the best dosage of SAC and silica fume added in Portland cement-based polyethylene fiber reinforced composite matrix material (PE-ECC), the PE-ECC material with the best reinforcement effect was obtained. This study can provide a new choice for the reinforcement repair project. In this study, the method of controlling control variables was used to analyze the compressive, tensile and three-point bending data of the specimens, and the optimal content of the two groups of PE-ECC materials with or without SAC was obtained. The lining thickness was insufficient. The model reinforcement comparison test method analyzes the data after the reinforcement of the two groups of PE-ECC materials with or without SAC at the optimal content. The results showed that the best dosage of SAC was S11 group (10 % SAC, 10 % silica fume), and the best dosage of SAC was S02 group (20 % silica fume). After adding an appropriate amount of SAC, the material reflects the early strength and high strength performance; the reinforcement effect of S11 group on the tunnel model with insufficient lining thickness is better than that of S02 group. This study finds out the SAC modified PE-ECC material with the best reinforcement effect, which provides a good material choice for rush repair and rush construction projects.